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Sample records for vision une perception

  1. Vision as subjective perception; La vision, une perception subjective

    Energy Technology Data Exchange (ETDEWEB)

    Reppas, J.B. [Harvard Univ., Cambridge, MA (United States). Biological Labs.; Dale, A.; Sereno, M.; Tootell, R.

    1996-07-01

    The human brain is not very different of the monkey`s one: at least, its visual cortex is organized as a similar scheme. Specialized areas in the movement analysis are found and others in the forms perception. In this work, the author tries to answer to the following questions: (1)why so many visual areas? What are exactly their role in vision? Thirteen years of experimentation have not allowed to answer to these questions. The cerebral NMR imaging gives the opportunity of understanding the subjective perception of the visual world. One step which is particularly described in this work is to know how the visual cortex reacts to the optical illusions. (O.M.).

  2. Une nouvelle vision de la transition en Syrie | CRDI - Centre de ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Une nouvelle vision de la transition en Syrie. 07 juin 2016. Bénéficiaire : Syrian Center for Political and Strategic Studies (SCPSS) Période visée : de juillet 2012 à août 2013. État : en cours de clôture. Financement accordé : 441 000 CAD. La Coalition nationale syrienne a officiellement donné son aval à une feuille de route ...

  3. Définition et révision d'une stratégie de développement industriel

    OpenAIRE

    Choffray, Jean-Marie; Wagner, Philippe

    1983-01-01

    L'objet de cet article est de présenter une approche nouvelle de définition et de révision de la stratégie d'une entreprise, reposant sur l'utilisation de l'Analyse des Processus Hiérarchiques. Nous présentons le modèle permettant de mesurer les priorités à établir entre les différents objectifs et actions possibles à chaque niveau de la hiérarchie. Peer reviewed

  4. LHC 2008 lectures "Une nouvelle vision du monde"

    CERN Multimedia

    2008-01-01

    The history of the science of the Universe and the science of matter have been marked by a small number of "revolutions" that have turned our understanding of the infinitesimally large and the infinitesimally small on its head. New ways of looking at the world have come about sometimes through conceptual advances and sometimes through innovations in scientific instrumentation. How do things stand at the beginning of the 21st century? Will today’s large-scale machine projects like the LHC and gravitational wave detectors pave the way for a new scientific revolution? Thursday, 15 May 2008 at 8.00 p.m. Une nouvelle vision du monde Jean-Pierre Luminet, Research Director at the CNRS The Globe, first floor No specialist knowledge required. Entrance free. To reserve call + 41 (0) 22 767 76 76 http://www.cern.ch/globe

  5. CANAL EMPLOI : une télévision éducative en devenir ?

    OpenAIRE

    Freres, Christian

    2013-01-01

    Dans un contexte de crise pour la chaîne de télévision éducative belge, Canal Emploi, l'auteur décrit le contexte audiovisuel belge, puis la genèse du projet pédagogique et didactique de Canal Emploi et, enfin, les perspectives de cette chaîne en 1987. Il développe, notamment, une stratégie audiovisuelle qui mêle pédagogie, didactique et outils marketing.

  6. Vision as subjective perception

    International Nuclear Information System (INIS)

    Reppas, J.B.; Dale, A.; Sereno, M.; Tootell, R.

    1996-01-01

    The human brain is not very different of the monkey's one: at least, its visual cortex is organized as a similar scheme. Specialized areas in the movement analysis are found and others in the forms perception. In this work, the author tries to answer to the following questions: 1)why so many visual areas? What are exactly their role in vision? Thirteen years of experimentation have not allowed to answer to these questions. The cerebral NMR imaging gives the opportunity of understanding the subjective perception of the visual world. One step which is particularly described in this work is to know how the visual cortex reacts to the optical illusions. (O.M.)

  7. Vers une vision surnaturelle de la folie

    Directory of Open Access Journals (Sweden)

    Mabel Franzone

    2006-12-01

    Full Text Available A partir de la difficile notion de "folie", il s’agit d’aller vers l’exclusion dont cette maladie a fait l’objet dans le système occidental moderne. Un autre traitement de la maladie mentale se fait jour avec des penseurs contemporains, la résurgence d’autres cosmovisions et de philosophies anciennes. Ainsi les délires mystique, paranoïaque, schizophrénique peuvent être étudiés d’une part comme des ruptures de limites, d’autre part comme une mise en relation du corps avec l’esprit. Entre les deux, le langage fait oeuvre de trait d’union, langage qui, chez les malades, dénote une créativité, la poésie. Si cette poésie permet une sortie, une explosion des limites de la réalité vers des régions inconnues, peut-être peut-on voir la folie comme un déséquilibre par rapport au monde, au cosmos même, déséquilibre qui peut être traité en responsabilisant l’homme, en le pensant, en le mettant en question. De ce point de vue, la folie ressort comme quelque chose de positif, comme l’un des thèmes qui nous repositionnera face au monde, en mettant à notre portée d’autres ontologies.

  8. Medical student and patient perceptions of quality of life associated with vision loss.

    Science.gov (United States)

    Chaudry, Imtiaz; Brown, Gary C; Brown, Melissa M

    2015-06-01

    Because most medical schools in the United States and Canada require no formal ophthalmology training, the authors queried medical student and ophthalmic patients to compare their perceptions of the quality of life (QOL) associated with vision loss. Cross-sectional comparative study of consecutive medical students and patients with vision loss using a validated, reliable, time trade-off utility instrument. Consecutive Jefferson Medical College medical students (cohort 1: 145 second-year student; cohort 2: 112 third-year/fourth-year students) and 283 patients with vision loss (patient cohort). Time trade-off vision utilities with anchors of 0.0 (death) to 1.0 (normal vision permanently) were used to quantify the QOL associated with vision loss. Students were asked to assume they had: (i) mild vision loss (20/40 to 20/50 vision in the better-seeing eye), (ii) legal blindness (20/200 in the better-seeing eye), and (iii) absolute blindness (no light perception bilaterally). Mean utilities for cohort 1/cohort 2 were 0.96/0.95 (p = 0.20) for mild vision loss, 0.88/0.84 for legal blindness (p = 0.009), and 0.80/0.67 (p student/patient mean utilities were 0.96/0.79 (p students underestimated the QOL associated with vision loss referent to patients with vision loss by 153%-425%. Medical students dramatically underestimated the impact of vision loss on patient QOL. Clinical training slightly improved medical student perceptions. Trivialization of vision loss could result in systemic health harm, less ophthalmic research dollars, loss of the finest medical students entering ophthalmology, and overall adverse financial effects for the field. Copyright © 2015. Published by Elsevier Inc.

  9. SYSTEME MULTISENSEUR DE PERCEPTION 3D POUR LE ROBOT MOBILE HILARE

    OpenAIRE

    Ferrer , Michel

    1982-01-01

    L'ETUDE PRESENTEE S'INSERE DANS LE VASTE DOMAINE DE LA VISION ARTIFICIELLE. ELLE CONCERNE PLUS PARTICULIEREMENT L'INTEGRATION DU SYSTEME DE PERCEPTION TROIS DIMENSIONS (3D) DU ROBOT MOBILE AUTONOME HILARE. CE SYSTEME EST COMPOSE D'UNE CAMERA MATRICIELLE A SEMICONDUCTEURS, D'UN TELEMETRE LASER ET D'UNE STRUCTURE MECANIQUE ASSURANT LA DEFLEXION DU FAISCEAU LASER. DANS CE MEMOIRE SONT DECRITS: LA CONCEPTION DE LA STRUCTURE DEFLECTRICE; LE LOGICIEL DE TRAITEMENT DES IMAGES VIDEO MULTINIVEAUX BASE...

  10. How the Venetian Blind Percept Emergesfrom the Laminar Cortical Dynamics of 3D Vision

    OpenAIRE

    Stephen eGrossberg

    2014-01-01

    The 3D LAMINART model of 3D vision and figure-ground perception is used to explain and simulate a key example of the Venetian blind effect and show how it is related to other well-known perceptual phenomena such as Panum's limiting case. The model shows how identified neurons that interact in hierarchically organized laminar circuits of the visual cortex can simulate many properties of 3D vision percepts, notably consciously seen surface percepts, which are predicted to arise when filled-in s...

  11. La Déclaration Universelle des Droits de l’Homme comme l’expression d’une vision du monde : une approche topique et génétique The Universal Declaration of Human Rights as an expression of a “vision of the world”: a topical and genetic perspective

    Directory of Open Access Journals (Sweden)

    Emmanuel de Jonge

    2010-04-01

    Full Text Available Dans cet article, je réalise une analyse de la Déclaration Universelle des Droits de l’Homme dans une perspective rhétorique et génétique. A l’aide des comptes rendus des débats préliminaires du Comité de Rédaction de la Déclaration, je montre que le texte a pour arrière-plan la volonté de fonder une vision du monde nouvelle, dans laquelle tout serait mis en œuvre d’un point de vue juridique, éthique, philosophique et psychologique pour que les actes subis par les populations européennes durant la Seconde Guerre Mondiale ne puissent plus se reproduire. Pour ce faire, j’analyse la question de l’expression linguistique des valeurs dans les deux premiers alinéas du préambule de la Déclaration.In this contribution, I analyze the text of the Universal Declaration of Human Rights from a rhetorical and genetic perspective. Starting from the summary reports of the Declaration Drafting Committee, I try to show that what lies at the background of the text is the feeling that the sufferings of WWII never can be reproduced. The drafters thus founded a new “vision of the world” that has shaped our values since then. I concentrate specifically on the first two lines of the preamble of the Declaration in order to analyze how the values are expressed linguistically in these paragraphs.

  12. Early vision impairs tactile perception in the blind.

    Science.gov (United States)

    Röder, Brigitte; Rösler, Frank; Spence, Charles

    2004-01-20

    Researchers have known for more than a century that crossing the hands can impair both tactile perception and the execution of appropriate finger movements. Sighted people find it more difficult to judge the temporal order when two tactile stimuli, one applied to either hand, are presented and their hands are crossed over the midline as compared to when they adopt a more typical uncrossed-hands posture. It has been argued that because of the dominant role of vision in motor planning and execution, tactile stimuli are remapped into externally defined coordinates (predominantly determined by visual inputs) that takes longer to achieve when external and body-centered codes (determined primarily by somatosensory/proprioceptive inputs) are in conflict and that involves both multisensory parietal and visual cortex. Here, we show that the performance of late, but not of congenitally, blind people was impaired by crossing the hands. Moreover, we provide the first empirical evidence for superior temporal order judgments (TOJs) for tactile stimuli in the congenitally blind. These findings suggest a critical role of childhood vision in modulating the perception of touch that may arise from the emergence of specific crossmodal links during development.

  13. Magnitude, precision, and realism of depth perception in stereoscopic vision.

    Science.gov (United States)

    Hibbard, Paul B; Haines, Alice E; Hornsey, Rebecca L

    2017-01-01

    Our perception of depth is substantially enhanced by the fact that we have binocular vision. This provides us with more precise and accurate estimates of depth and an improved qualitative appreciation of the three-dimensional (3D) shapes and positions of objects. We assessed the link between these quantitative and qualitative aspects of 3D vision. Specifically, we wished to determine whether the realism of apparent depth from binocular cues is associated with the magnitude or precision of perceived depth and the degree of binocular fusion. We presented participants with stereograms containing randomly positioned circles and measured how the magnitude, realism, and precision of depth perception varied with the size of the disparities presented. We found that as the size of the disparity increased, the magnitude of perceived depth increased, while the precision with which observers could make depth discrimination judgments decreased. Beyond an initial increase, depth realism decreased with increasing disparity magnitude. This decrease occurred well below the disparity limit required to ensure comfortable viewing.

  14. Clinical Tests of Ultra-Low Vision Used to Evaluate Rudimentary Visual Perceptions Enabled by the BrainPort Vision Device.

    Science.gov (United States)

    Nau, Amy; Bach, Michael; Fisher, Christopher

    2013-01-01

    We evaluated whether existing ultra-low vision tests are suitable for measuring outcomes using sensory substitution. The BrainPort is a vision assist device coupling a live video feed with an electrotactile tongue display, allowing a user to gain information about their surroundings. We enrolled 30 adult subjects (age range 22-74) divided into two groups. Our blind group included 24 subjects ( n = 16 males and n = 8 females, average age 50) with light perception or worse vision. Our control group consisted of six subjects ( n = 3 males, n = 3 females, average age 43) with healthy ocular status. All subjects performed 11 computer-based psychophysical tests from three programs: Basic Assessment of Light Motion, Basic Assessment of Grating Acuity, and the Freiburg Vision Test as well as a modified Tangent Screen. Assessments were performed at baseline and again using the BrainPort after 15 hours of training. Most tests could be used with the BrainPort. Mean success scores increased for all of our tests except contrast sensitivity. Increases were statistically significant for tests of light perception (8.27 ± 3.95 SE), time resolution (61.4% ± 3.14 SE), light localization (44.57% ± 3.58 SE), grating orientation (70.27% ± 4.64 SE), and white Tumbling E on a black background (2.49 logMAR ± 0.39 SE). Motion tests were limited by BrainPort resolution. Tactile-based sensory substitution devices are amenable to psychophysical assessments of vision, even though traditional visual pathways are circumvented. This study is one of many that will need to be undertaken to achieve a common outcomes infrastructure for the field of artificial vision.

  15. Enhanced operator perception through 3D vision and haptic feedback

    Science.gov (United States)

    Edmondson, Richard; Light, Kenneth; Bodenhamer, Andrew; Bosscher, Paul; Wilkinson, Loren

    2012-06-01

    Polaris Sensor Technologies (PST) has developed a stereo vision upgrade kit for TALON® robot systems comprised of a replacement gripper camera and a replacement mast zoom camera on the robot, and a replacement display in the Operator Control Unit (OCU). Harris Corporation has developed a haptic manipulation upgrade for TALON® robot systems comprised of a replacement arm and gripper and an OCU that provides haptic (force) feedback. PST and Harris have recently collaborated to integrate the 3D vision system with the haptic manipulation system. In multiple studies done at Fort Leonard Wood, Missouri it has been shown that 3D vision and haptics provide more intuitive perception of complicated scenery and improved robot arm control, allowing for improved mission performance and the potential for reduced time on target. This paper discusses the potential benefits of these enhancements to robotic systems used for the domestic homeland security mission.

  16. The Indirect Perception of Distance: Interpretive Complexities in Berkeley's Theory of Vision

    Directory of Open Access Journals (Sweden)

    Michael James Braund

    2007-12-01

    Full Text Available The problem of whether perception is direct or if it depends on additional, cognitive contributions made by the perceiving subject, is posed with particular force in an Essay towards a New Theory of Vision (NTV. It is evident from the recurrent treatment it receives therein that Berkeley considers it to be one of the central issues concerning perception. Fittingly, the NTV devotes the most attention to it. In this essay, I deal exclusively with Berkeley's treatment of the problem of indirect distance perception, as it is presented in the context of that work.

  17. Perceptions Matter: Administrators' Vision of Instruction for Students with Severe Disabilities

    Science.gov (United States)

    Roberts, Carly A.; Ruppar, Andrea L.; Olson, Amy J.

    2018-01-01

    School administrators play an important role in shaping teaching and learning. However, very little is known regarding how school administrators perceive instruction for students with severe disabilities and how those perceptions shape expectations and visions for instruction. Semistructured interviews were used to interview 12 administrators…

  18. Exploring public perception of non-native species from a visions of nature perspective.

    Science.gov (United States)

    Verbrugge, Laura N H; Van den Born, Riyan J G; Lenders, H J Rob

    2013-12-01

    Not much is known about lay public perceptions of non-native species and their underlying values. Public awareness and engagement, however, are important aspects in invasive species management. In this study, we examined the relations between the lay public's visions of nature, their knowledge about non-native species, and their perceptions of non-native species and invasive species management with a survey administered in the Netherlands. Within this framework, we identified three measures for perception of non-native species: perceived risk, control and engagement. In general, respondents scored moderate values for perceived risk and personal engagement. However, in case of potential ecological or human health risks, control measures were supported. Respondents' images of the human-nature relationship proved to be relevant in engagement in problems caused by invasive species and in recognizing the need for control, while images of nature appeared to be most important in perceiving risks to the environment. We also found that eradication of non-native species was predominantly opposed for species with a high cuddliness factor such as mammals and bird species. We conclude that lay public perceptions of non-native species have to be put in a wider context of visions of nature, and we discuss the implications for public support for invasive species management.

  19. LE SOLUTRÉEN ANCIEN EN ARDÈCHE (FRANCE: UNEVISION CRITIQUE DES INDUSTRIES LITHIQUES

    Directory of Open Access Journals (Sweden)

    Sophie Guegan

    2013-11-01

    Full Text Available S’inscrivant dans un travail de Doctorat sur les peuplements des deux rives de la vallée du Rhône au Maximum Glaciaire, cet article propose un état des connaissances sur la phase ancienne du Solutréen en Ardèche (rive droite du Rhône, donnant lieu à unevision critique des industries lithiques s’y rapportant. En effet, depuis les travaux de P.E.L. Smith et J. Combier, et plus récemment le travail d’A. Barbiero consacré aux pointes à face plance et pointes à cran d’une collection ancienne à la Baume d’Oullins (Gard-Ardèche, France, aucun réexamen global n’avait été entrepris. Trois gisements de référence pour cette phase ancienne, ont ainsi été sélectionnés: les grottes d’Oullins (Gard-Ardèche, France, de Chabot (Gard, France et de Granouly (Ardèche, France. Nous présentons ici les réslutats préliminaires à cette étude. En premier lieu, une approche typologique a été menée principalement autour de la pointe à face plane, objet emblématique de cette phase, permettant d’en préciser les principaux caractères. Dans un deuxième temps, une approche technologique a permis de confirmer l’homogénéité dans les choix techniques des Solutréens entre l’Ardèche et les régions du Sud-Ouest et du Bassin Parisien. Enfin, une étude des matières premières, a révélé pour l’heure des choix économiques étonnants pour le contexte paléo-climatique, avec des déplacements vers le nords et un franchissement du Rhône.In the frame of a doctoral dissertation on the Late Glacial Maximum occupations of both sides of the Rhône valley, this paper presents a state of the art and a critical reappraisal of the lithic assemblages from the early phases of the Solutrean in Ardeche (right bank of the Rhône river. Indeed, since the works of P.E.L. Smith and J. Combier, except the work of A. Barbiero, on the unifacial leaf-points and shouldered points from Baume d'Oullins, no complete study of these

  20. Playing with Senses in VR: Alternate Perceptions Combining Vision and Touch.

    Science.gov (United States)

    Lecuyer, Anatole

    2017-01-01

    Virtual reality is an immersive experience based on computer-generated stimulations perceived with multiple sensory channels. It is possible to manipulate these sensory stimulations independently and create conflicting situations in which, for instance, vision and touch are spatially and/or temporally inconsistent. This article discusses how to exploit these ambiguous sensorial situations to generate new kinds of percept using three types of examples: pseudo-haptic effects, self-motion sensations, and body-ownership illusions.

  1. Shape perception in human and computer vision an interdisciplinary perspective

    CERN Document Server

    Dickinson, Sven J

    2013-01-01

    This comprehensive and authoritative text/reference presents a unique, multidisciplinary perspective on Shape Perception in Human and Computer Vision. Rather than focusing purely on the state of the art, the book provides viewpoints from world-class researchers reflecting broadly on the issues that have shaped the field. Drawing upon many years of experience, each contributor discusses the trends followed and the progress made, in addition to identifying the major challenges that still lie ahead. Topics and features: examines each topic from a range of viewpoints, rather than promoting a speci

  2. Visual Problems in Night Operations (Problemes de Vision dans les Operations de Nuit)

    Science.gov (United States)

    1992-05-01

    conference proceedings (FR) Progrqbs r~cents concernant l05 aides au pilote clans I habitacle d’un aaroi’ef milltaire en operations. Nouveau drone ...allleurs) traitelit doe la sophistication des La firme isra~lienne tAt teste un nouveau drone appel6 ’Impact’. tacnes domanda~es aus pilotes d-avionS- doe...une camara do tala6vision A vision nocturne. 151 met aussl relations liomlme-macfline.ces syst~mws (lndiff~remesmnt dasignds au point une station

  3. How the venetian blind percept emerges from the laminar cortical dynamics of 3D vision

    OpenAIRE

    Cao, Yongqiang; Grossberg, Stephen

    2014-01-01

    The 3D LAMINART model of 3D vision and figure-ground perception is used to explain and simulate a key example of the Venetian blind effect and to show how it is related to other well-known perceptual phenomena such as Panum's limiting case. The model proposes how lateral geniculate nucleus (LGN) and hierarchically organized laminar circuits in cortical areas V1, V2, and V4 interact to control processes of 3D boundary formation and surface filling-in that simulate many properties of 3D vision ...

  4. An Emphasis on Perception: Teaching Image Formation Using a Mechanistic Model of Vision.

    Science.gov (United States)

    Allen, Sue; And Others

    An effective way to teach the concept of image is to give students a model of human vision which incorporates a simple mechanism of depth perception. In this study two almost identical versions of a curriculum in geometrical optics were created. One used a mechanistic, interpretive eye model, and in the other the eye was modeled as a passive,…

  5. How the Venetian Blind Percept Emergesfrom the Laminar Cortical Dynamics of 3D Vision

    Directory of Open Access Journals (Sweden)

    Stephen eGrossberg

    2014-08-01

    Full Text Available The 3D LAMINART model of 3D vision and figure-ground perception is used to explain and simulate a key example of the Venetian blind effect and show how it is related to other well-known perceptual phenomena such as Panum's limiting case. The model shows how identified neurons that interact in hierarchically organized laminar circuits of the visual cortex can simulate many properties of 3D vision percepts, notably consciously seen surface percepts, which are predicted to arise when filled-in surface representations are integrated into surface-shroud resonances between visual and parietal cortex. The model describes how monocular and binocular oriented filtering interacts with later stages of 3D boundary formation and surface filling-in in the lateral geniculate nucleus (LGN and cortical areas V1, V2, and V4. It proposes how interactions between layers 4, 3B, and 2/3 in V1 and V2 contribute to stereopsis, and how binocular and monocular information combine to form 3D boundary and surface representations. The model suggests how surface-to-boundary feedback from V2 thin stripes to pale stripes enables computationally complementary boundary and surface formation properties to generate a single consistent percept, eliminate redundant 3D boundaries, and trigger figure-ground perception. The model also shows how false binocular boundary matches may be eliminated by Gestalt grouping properties. In particular, a disparity filter, which helps to solve the Correspondence Problem by eliminating false matches, is predicted to be realized as part of the boundary grouping process in layer 2/3 of cortical area V2. The model has been used to simulate the consciously seen 3D surface percepts in 18 psychophysical experiments. These percepts include the Venetian blind effect, Panum's limiting case, contrast variations of dichoptic masking and the correspondence problem, the effect of interocular contrast differences on stereoacuity, stereopsis with polarity

  6. Genetics Home Reference: color vision deficiency

    Science.gov (United States)

    ... my area? Other Names for This Condition color blindness color vision defects defective color vision vision defect, color ... Perception KidsHealth from the Nemours Foundation MalaCards: color blindness MalaCards: color vision deficiency Orphanet: Blue cone monochromatism Orphanet: NON ...

  7. Une nouvelle vision pour AfricaAdapt – Entrevue avec Moussa Na ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    24 févr. 2011 ... Réseau panafricain lancé en mai 2009, AfricaAdapt vient de recevoir le feu vert pour l'exécution d'une nouvelle phase d'activités de deux ans, qu'appuie le programme Adaptation aux changements climatiques en Afrique.

  8. How the venetian blind percept emerges from the laminar cortical dynamics of 3D vision.

    Science.gov (United States)

    Cao, Yongqiang; Grossberg, Stephen

    2014-01-01

    The 3D LAMINART model of 3D vision and figure-ground perception is used to explain and simulate a key example of the Venetian blind effect and to show how it is related to other well-known perceptual phenomena such as Panum's limiting case. The model proposes how lateral geniculate nucleus (LGN) and hierarchically organized laminar circuits in cortical areas V1, V2, and V4 interact to control processes of 3D boundary formation and surface filling-in that simulate many properties of 3D vision percepts, notably consciously seen surface percepts, which are predicted to arise when filled-in surface representations are integrated into surface-shroud resonances between visual and parietal cortex. Interactions between layers 4, 3B, and 2/3 in V1 and V2 carry out stereopsis and 3D boundary formation. Both binocular and monocular information combine to form 3D boundary and surface representations. Surface contour surface-to-boundary feedback from V2 thin stripes to V2 pale stripes combines computationally complementary boundary and surface formation properties, leading to a single consistent percept, while also eliminating redundant 3D boundaries, and triggering figure-ground perception. False binocular boundary matches are eliminated by Gestalt grouping properties during boundary formation. In particular, a disparity filter, which helps to solve the Correspondence Problem by eliminating false matches, is predicted to be realized as part of the boundary grouping process in layer 2/3 of cortical area V2. The model has been used to simulate the consciously seen 3D surface percepts in 18 psychophysical experiments. These percepts include the Venetian blind effect, Panum's limiting case, contrast variations of dichoptic masking and the correspondence problem, the effect of interocular contrast differences on stereoacuity, stereopsis with polarity-reversed stereograms, da Vinci stereopsis, and perceptual closure. These model mechanisms have also simulated properties of 3D neon

  9. Le jeu problématique : une pathologie, un échec d’autorégulation ou une question sociale ?

    Directory of Open Access Journals (Sweden)

    Virve Marionneau

    2016-04-01

    Full Text Available Dans les débats académiques académiques ainsi que dans le débat public, le jeu problématique est souvent perçu soit comme une affection médicale et psychiatrique, soit comme étant de la responsabilité de l’individu qui joue. Les sociologues, en particulier, ont critiqué ces deux perspectives individualistes du jeu problématique, en avançant l’argument que le jeu n’a pas de sens inné, mais que sa définition dépend des conditions sociales. Au cours de cette discussion nous retracerons les racines de ces deux propos afin de montrer que les définitions sociales des jeux de hasard et d’argent de même que du jeu problématique dépendent de l’époque, des disciplines académiques et des contextes socioculturels. En poursuivant la réflexion en ce sens, nous proposerons ici de passer d’un point de vue individualiste à une vision plus sociale du jeu problématique au regard de la santé publique. En effet, en décloisonnant la prise en compte des conséquences du jeu problématique au seul individu et en élargissant la prise en compte de celles-ci à son entourage mais aussi à sa communauté, on attribue alors les problèmes à des comportements et non plus uniquement à des individus. Cette perspective permettrait dès lors d’avoir une vision plus globale et moins centrée sur l’individu, des problèmes liés aux jeux tout en discutant également de la responsabilité de l’industrie du jeu et des acteurs étatiques.

  10. Recherches sur l’apocalyptique syriaque et byzantine au viie siècle : la place de l’Empire romain dans une histoire du salut

    Directory of Open Access Journals (Sweden)

    Pablo Ubierna

    2009-02-01

    Full Text Available L’occupation perse et la littérature apocalyptiqueLa perception des événements militaires du début du viie siècle – d’abord l’occupation perse et ensuite la guerre arabe – n’est pas écartée, chez les contemporains, de la vision d’un empire, l’empire byzantin, secoué par de fortes controverses religieuses.La préoccupation intellectuelle à propos de la situation de l’Empire fut extrêmement marquée au commencement du viie siècle. Une vie anonyme de l’empereur Maurice inclut un récit de sa mort d...

  11. Perception of linear horizontal self-motion induced by peripheral vision /linearvection/ - Basic characteristics and visual-vestibular interactions

    Science.gov (United States)

    Berthoz, A.; Pavard, B.; Young, L. R.

    1975-01-01

    The basic characteristics of the sensation of linear horizontal motion have been studied. Objective linear motion was induced by means of a moving cart. Visually induced linear motion perception (linearvection) was obtained by projection of moving images at the periphery of the visual field. Image velocity and luminance thresholds for the appearance of linearvection have been measured and are in the range of those for image motion detection (without sensation of self motion) by the visual system. Latencies of onset are around 1 sec and short term adaptation has been shown. The dynamic range of the visual analyzer as judged by frequency analysis is lower than the vestibular analyzer. Conflicting situations in which visual cues contradict vestibular and other proprioceptive cues show, in the case of linearvection a dominance of vision which supports the idea of an essential although not independent role of vision in self motion perception.

  12. Peripheral vision of youths with low vision: motion perception, crowding, and visual search.

    Science.gov (United States)

    Tadin, Duje; Nyquist, Jeffrey B; Lusk, Kelly E; Corn, Anne L; Lappin, Joseph S

    2012-08-24

    Effects of low vision on peripheral visual function are poorly understood, especially in children whose visual skills are still developing. The aim of this study was to measure both central and peripheral visual functions in youths with typical and low vision. Of specific interest was the extent to which measures of foveal function predict performance of peripheral tasks. We assessed central and peripheral visual functions in youths with typical vision (n = 7, ages 10-17) and low vision (n = 24, ages 9-18). Experimental measures used both static and moving stimuli and included visual crowding, visual search, motion acuity, motion direction discrimination, and multitarget motion comparison. In most tasks, visual function was impaired in youths with low vision. Substantial differences, however, were found both between participant groups and, importantly, across different tasks within participant groups. Foveal visual acuity was a modest predictor of peripheral form vision and motion sensitivity in either the central or peripheral field. Despite exhibiting normal motion discriminations in fovea, motion sensitivity of youths with low vision deteriorated in the periphery. This contrasted with typically sighted participants, who showed improved motion sensitivity with increasing eccentricity. Visual search was greatly impaired in youths with low vision. Our results reveal a complex pattern of visual deficits in peripheral vision and indicate a significant role of attentional mechanisms in observed impairments. These deficits were not adequately captured by measures of foveal function, arguing for the importance of independently assessing peripheral visual function.

  13. Peripheral Vision of Youths with Low Vision: Motion Perception, Crowding, and Visual Search

    Science.gov (United States)

    Tadin, Duje; Nyquist, Jeffrey B.; Lusk, Kelly E.; Corn, Anne L.; Lappin, Joseph S.

    2012-01-01

    Purpose. Effects of low vision on peripheral visual function are poorly understood, especially in children whose visual skills are still developing. The aim of this study was to measure both central and peripheral visual functions in youths with typical and low vision. Of specific interest was the extent to which measures of foveal function predict performance of peripheral tasks. Methods. We assessed central and peripheral visual functions in youths with typical vision (n = 7, ages 10–17) and low vision (n = 24, ages 9–18). Experimental measures used both static and moving stimuli and included visual crowding, visual search, motion acuity, motion direction discrimination, and multitarget motion comparison. Results. In most tasks, visual function was impaired in youths with low vision. Substantial differences, however, were found both between participant groups and, importantly, across different tasks within participant groups. Foveal visual acuity was a modest predictor of peripheral form vision and motion sensitivity in either the central or peripheral field. Despite exhibiting normal motion discriminations in fovea, motion sensitivity of youths with low vision deteriorated in the periphery. This contrasted with typically sighted participants, who showed improved motion sensitivity with increasing eccentricity. Visual search was greatly impaired in youths with low vision. Conclusions. Our results reveal a complex pattern of visual deficits in peripheral vision and indicate a significant role of attentional mechanisms in observed impairments. These deficits were not adequately captured by measures of foveal function, arguing for the importance of independently assessing peripheral visual function. PMID:22836766

  14. Artificial Vision, New Visual Modalities and Neuroadaptation

    Directory of Open Access Journals (Sweden)

    Hilmi Or

    2012-01-01

    Full Text Available To study the descriptions from which artificial vision derives, to explore the new visual modalities resulting from eye surgeries and diseases, and to gain awareness of the use of machine vision systems for both enhancement of visual perception and better understanding of neuroadaptation. Science could not define until today what vision is. However, some optical-based systems and definitions have been established considering some factors for the formation of seeing. The best known system includes Gabor filter and Gabor patch which work on edge perception, describing the visual perception in the best known way. These systems are used today in industry and technology of machines, robots and computers to provide their "seeing". These definitions are used beyond the machinery in humans for neuroadaptation in new visual modalities after some eye surgeries or to improve the quality of some already known visual modalities. Beside this, “the blindsight” -which was not known to exist until 35 years ago - can be stimulated with visual exercises. Gabor system is a description of visual perception definable in machine vision as well as in human visual perception. This system is used today in robotic vision. There are new visual modalities which arise after some eye surgeries or with the use of some visual optical devices. Also, blindsight is a different visual modality starting to be defined even though the exact etiology is not known. In all the new visual modalities, new vision stimulating therapies using the Gabor systems can be applied. (Turk J Oph thal mol 2012; 42: 61-5

  15. La Santé: Une Approche Écosystémique

    International Development Research Centre (IDRC) Digital Library (Canada)

    Le défi consiste à satisfaire les besoins humains sans altérer ni mettre en danger ... L'évolution de cette science a influencé la réflexion de médecins comme le docteur ... Pour les artisans d'une vision globale, l'humain et ses aspirations, son .... coûteux que bien des soins médicaux et des interventions en santé primaire.

  16. Une nouvelle vision de la transition en Syrie | CRDI - Centre de ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Voilà bientôt deux ans que la situation en Syrie va de mal en pis et continue de se dégrader à un rythme affolant. Les efforts déployés sur la scène internationale ont toujours pour but d'en arriver à une solution politique, notamment à un plan de transition. Or, l'opposition syrienne, elle, a besoin d'énoncer clairement sa ...

  17. S'appuyer sur l'ergonomie pour concevoir une machine directive "Machines" 2006/42/CE

    CERN Document Server

    Bossard, Pascale; Grandjacques, Benoît; Seitier, Sylvie; Thibault, Jean-François

    2012-01-01

    L'ergonomie est désormais au centre des préoccupations dès lors qu'il s'agit de concevoir des machines. Pour le législateur, très alerte vis-à-vis de cette problématique, l'objectif est avant tout d'aboutir à une meilleure préservation de la santé et de la sécurité des opérateurs. Cet ouvrage, oeuvre commune du Cetim, de la FIM et de l'Anact, a pour objectif de mettre à disposition une méthode commune qui intègre à la fois prévention, notamment des facteurs de pénibilité, réglementation, normalisation et ergonomie. Une publication inédite mêlant deux approches pour une méthodologie commune : celle de l'ingénieur industriel oeuvrant pour l'intégration de la sécurité des machines et la vision d'une agence nationale intervenant dans le domaine de l'amélioration des conditions de travail, en particulier de l'ergonomie.

  18. Une vision partagée des situations de soins

    Directory of Open Access Journals (Sweden)

    Isabelle BAYLE

    2012-12-01

    Full Text Available Toutes les situations de travail sont singulières. Travailler c’est faire des choix en action. Alors comment le professionnel infirmier transmet-il son savoir de soignant ? Comment parle-t-il de son activité infirmière pour la rendre plus lisible à l’apprenant ? Comment développer un agir sensé, réfléchi, chez l’étudiant ? Cela va peut-être demander de réfléchir au sens de l’humanité, de l’humain et, de ce fait, accompagner l’étudiant dans le développement de compétences en situation de travail, avec le souci d’une véritable éthique du quotidien.

  19. Low Vision Care: The Need to Maximise Visual Potential

    Directory of Open Access Journals (Sweden)

    Ramachandra Pararajasegaram

    2004-01-01

    Full Text Available People with low vision have residual vision with some light perception, but their vision loss does not lend itself to improvement by standard spectacles or medical or surgical treatment. Such persons have the potential for enhanced functional vision if they receive appropriate low vision care services.

  20. Vision-Related Quality of Life Associated with Unilateral and Bilateral Ocular Conditions.

    Science.gov (United States)

    Brown, Gary C; Brown, Melissa M; Stein, Joshua D; Smiddy, William E

    2018-02-21

    To present ophthalmic patient time-tradeoff vision utilities for quantifying vision-related quality-of-life when the fellow eye still has good vision. These utilities are important for performing reliable cost-utility analyses. Consecutive time-tradeoff vision utilities were obtained from ophthalmic patients with good vision (20/20-20/25) in one eye and vision ranging from 20/20 to no light perception in the fellow eye over a 15-year period from 2000 through 2014. Five hundred eighty-six ophthalmic participant interviews from Wills Eye Hospital, New York Eye and Ear Hospital, and ophthalmology office practices in Pennsylvania and New Jersey. Participants underwent a full ophthalmic examination, after which time-tradeoff vision utilities were obtained by personal interview by the authors using a standardized, validated instrument. Time-tradeoff vision utilities. Mean time-tradeoff vision utilities were as follows in participants with good vision (20/20-20/25) in at least one eye and the following visions in the fellow eyes: no light perception, 0.79; counting fingers to light perception, 0.87; 20/200 to 20/400, 0.88; 20/60 to 20/100, 0.88; 20/30 to 20/50, 0.87; and 20/20 to 20/25, 0.94. In people with good vision (20/20-20/25) in one eye, the associated mean time-tradeoff vision utility is a remarkably consistent 0.87 to 0.88 when vision in the fellow eye ranges from 20/30 to light perception. Vision of 20/20 to 20/25 in the fellow eye results in a significantly higher associated utility of 0.94 (P vision of no light perception in the fellow eye results in a significantly lower utility of 0.079 (P < 0.01). These utilities are important for calculating reliable patient value (quality-adjusted life-year) gains in ophthalmic cost-utility analysis populations in which there is unilateral and bilateral disease involvement. Copyright © 2018 American Academy of Ophthalmology. Published by Elsevier Inc. All rights reserved.

  1. Management : pour une recherche de la qualité en milieu hospitalier

    OpenAIRE

    Aldo Perissino

    2011-01-01

    Avec l’avènement de la technologie médicale, l’hôpital est devenu le symbole d’une médecine de pointe, que la sécurité sociale se devait de rendre accessible à tous. Sur cette vision de progrès développée dans l’après-guerre et les « golden sixties » s’est construite une inflation hospitalière que l’évolution économique a progressivement rendue de plus en plus intenable, imposant au secteur des mesures de contrôle budgétaire sévères. Parallèlement, le souci de la qualité des services offerts,...

  2. Low Vision Devices and Training

    Directory of Open Access Journals (Sweden)

    Imran Azam Butt

    2004-01-01

    Full Text Available Vision is the ability to see with a clear perception of detail, colour and contrast, and to distinguish objects visually. Like any other sense, vision tends to deteriorate or diminish naturally with age. In most cases, reduction in visual capability can be corrected with glasses, medicine or surgery. However, if the visual changes occur because of an incurable eye disease, condition or injury, vision loss can be permanent. Many people around the world with permanent visual impairment have some residual vision which can be used with the help of low vision services, materials and devices. This paper describes different options for the enhancement of residual vision including optical and non-optical devices and providing training for the low vision client.

  3. Key Informant Perceptions of Vision Loss in Children and ...

    African Journals Online (AJOL)

    tulyasys

    understand how vision can practically be assessed and how poor vision can affect a child, whether by limiting the ability to do activities of daily living or by limiting social interactions. In this group, there were some misconceptions regarding the use of color vision and the assessment of reading as a tool for vision assessment ...

  4. Vision-Based Perception and Classification of Mosquitoes Using Support Vector Machine

    Directory of Open Access Journals (Sweden)

    Masataka Fuchida

    2017-01-01

    Full Text Available The need for a novel automated mosquito perception and classification method is becoming increasingly essential in recent years, with steeply increasing number of mosquito-borne diseases and associated casualties. There exist remote sensing and GIS-based methods for mapping potential mosquito inhabitants and locations that are prone to mosquito-borne diseases, but these methods generally do not account for species-wise identification of mosquitoes in closed-perimeter regions. Traditional methods for mosquito classification involve highly manual processes requiring tedious sample collection and supervised laboratory analysis. In this research work, we present the design and experimental validation of an automated vision-based mosquito classification module that can deploy in closed-perimeter mosquito inhabitants. The module is capable of identifying mosquitoes from other bugs such as bees and flies by extracting the morphological features, followed by support vector machine-based classification. In addition, this paper presents the results of three variants of support vector machine classifier in the context of mosquito classification problem. This vision-based approach to the mosquito classification problem presents an efficient alternative to the conventional methods for mosquito surveillance, mapping and sample image collection. Experimental results involving classification between mosquitoes and a predefined set of other bugs using multiple classification strategies demonstrate the efficacy and validity of the proposed approach with a maximum recall of 98%.

  5. Pre-attentive and attentive vision module

    NARCIS (Netherlands)

    Nyamsuren, Enkhbold; Taatgen, Niels A.

    This paper introduces a new vision module, called PAAV, developed for the cognitive architecture ACT-R. Unlike ACT-R's default vision module that was originally developed for top-down perception only, PAAV was designed to model a wide range of tasks, such as visual search and scene viewing, where

  6. Perception of 3-D location based on vision, touch, and extended touch.

    Science.gov (United States)

    Giudice, Nicholas A; Klatzky, Roberta L; Bennett, Christopher R; Loomis, Jack M

    2013-01-01

    Perception of the near environment gives rise to spatial images in working memory that continue to represent the spatial layout even after cessation of sensory input. As the observer moves, these spatial images are continuously updated. This research is concerned with (1) whether spatial images of targets are formed when they are sensed using extended touch (i.e., using a probe to extend the reach of the arm) and (2) the accuracy with which such targets are perceived. In Experiment 1, participants perceived the 3-D locations of individual targets from a fixed origin and were then tested with an updating task involving blindfolded walking followed by placement of the hand at the remembered target location. Twenty-four target locations, representing all combinations of two distances, two heights, and six azimuths, were perceived by vision or by blindfolded exploration with the bare hand, a 1-m probe, or a 2-m probe. Systematic errors in azimuth were observed for all targets, reflecting errors in representing the target locations and updating. Overall, updating after visual perception was best, but the quantitative differences between conditions were small. Experiment 2 demonstrated that auditory information signifying contact with the target was not a factor. Overall, the results indicate that 3-D spatial images can be formed of targets sensed by extended touch and that perception by extended touch, even out to 1.75 m, is surprisingly accurate.

  7. La traversée de l'Atlantique ou la mort ? Une réflexion critique sur la ...

    African Journals Online (AJOL)

    19 mars 2018 ... physique et naturel, trouvera une interprétation figurative dans cet article. Il s'agit ... Il va de soi que dans certaines ... soi dans la vision du monde d'un sujet. ..... Cependant en terme de créolisation, Glissant estime que: “La ...

  8. Relationship between Stereoscopic Vision, Visual Perception, and Microstructure Changes of Corpus Callosum and Occipital White Matter in the 4-Year-Old Very Low Birth Weight Children

    Directory of Open Access Journals (Sweden)

    Przemko Kwinta

    2015-01-01

    Full Text Available Aim. To assess the relationship between stereoscopic vision, visual perception, and microstructure of the corpus callosum (CC and occipital white matter, 61 children born with a mean birth weight of 1024 g (SD 270 g were subjected to detailed ophthalmologic evaluation, Developmental Test of Visual Perception (DTVP-3, and diffusion tensor imaging (DTI at the age of 4. Results. Abnormal stereoscopic vision was detected in 16 children. Children with abnormal stereoscopic vision had smaller CC (CC length: 53±6 mm versus 61±4 mm; p<0.01; estimated CC area: 314±106 mm2 versus 446±79 mm2; p<0.01 and lower fractional anisotropy (FA values in CC (FA value of rostrum/genu: 0.7±0.09 versus 0.79±0.07; p<0.01; FA value of CC body: 0.74±0.13 versus 0.82±0.09; p=0.03. We found a significant correlation between DTVP-3 scores, CC size, and FA values in rostrum and body. This correlation was unrelated to retinopathy of prematurity. Conclusions. Visual perceptive dysfunction in ex-preterm children without major sequelae of prematurity depends on more subtle changes in the brain microstructure, including CC. Role of interhemispheric connections in visual perception might be more complex than previously anticipated.

  9. Vers une esthétique de la science-fiction

    Directory of Open Access Journals (Sweden)

    Joanna Russ

    2013-04-01

    Full Text Available Les outils critiques élaborés en ayant à l’esprit une littérature entièrement différente ne fonctionnent pas quand ils sont appliqués à la science-fiction. Dans cet article, j’avance la proposition suivante : que la science-fiction est didactique. Malgré des similitudes superficielles avec la fiction moderne naturaliste (ou autre, les personnages de science-fiction sont toujours des personnes collectives, jamais individuelles. Je suggère que la critique littéraire contemporaine n’est pas l’outil idéal pour traiter de fiction didactique, ou pour évaluer une littérature nouvelle et différente. Appliquer les critères et les méthodes auxquels nous sommes habitués ne peut mener qu’à trois résultats : le rejet de toute science-fiction comme n’étant pas de la littérature, une préférence pour certains genres restreints de science-fiction (parce qu’on peut les comprendre au moins partiellement selon la manière habituelle, ou une conception et une perception erronées des textes que l’on essaie précisément de comprendre. La troisième catégorie est restée rare jusqu’ici, parce que l’intérêt universitaire pour la science-fiction était rare, mais elle pourrait devenir bien trop courante si la popularité croissante des cours d’université sur ce sujet ne s’accompagne pas d’une critique adaptée à son sujet.

  10. Faculty Perceptions of Strategic Visioning.

    Science.gov (United States)

    Marcus, Laurence R.; Smith, Richard

    This report presents an examination of the use of a participative model in the strategic planning process at a publicly-supported, comprehensive institution in the middle Atlantic region of the United States. Specific attention is given to the process of developing the vision statement, an undertaking of approximately 15 months preceding Board of…

  11. La vision de Saint Eustathe dans la peinture post-byzantine

    Directory of Open Access Journals (Sweden)

    Amprazogoula Katerina

    2008-01-01

    Full Text Available (francuski L'article étudie l'évolution de la Vision de saint Eustathe dans une série de peintures murales et d'icônes portatives - allant du XVIe au XVIIIe siècle - les formules iconographiques adoptées et leurs particularités ainsi que la place et la fonction de cette image dans la peinture murale. Le matériel étudié a montré une diversité de formules iconographiques qui exploitent pour l'essentiel la tradition byzantine et orientale du sujet, en manifestant en même temps ses propres traits ainsi que l'influence des images occidentales. .

  12. Réponse à Mme DESAFY-GRIGNARD au sujet de son ouvrage Arthur Miller : une vie à l’œuvre

    Directory of Open Access Journals (Sweden)

    Trudy Bolter

    2006-11-01

    Full Text Available RÉPONSE à Mme DESAFY-GRIGNARD 
au sujet de son ouvrage Arthur Miller : une vie à l’oeuvre


 Un compte rendu n’est pas forcément un résumé neutre : rien ne m’oblige à répéter en l’étoffant la quatrième page de couverture de l'ouvrage. « Lu par ... » dit bien qu'il s'agit d'une vision personnelle. J’avoue que j’ai lu ce livre avec surprise, une émotion très vive, pas toujours très positive. Je conteste certaines approches, qui m’apparaissent approximatives, pas assez complètes , quelques tourn...

  13. 75 FR 9480 - Qualification of Drivers; Exemption Applications; Vision

    Science.gov (United States)

    2010-03-02

    ... injury sustained as a child. The best corrected visual acuity in his right eye is light-perception only... medical opinion, Mr. Williford has sufficient visual acuity, color vision and peripheral vision to perform...

  14. Pre-Service Teacher Vision and Urban Schools

    Science.gov (United States)

    Roselle, Rene; Liner, Kevin

    2012-01-01

    As preservice teachers enter their first teaching experience, they often have perceptions about what teaching will be like based on a vision that is typically linked to their own background and experiences. This study explores the changes in visions of 15 preservice teachers throughout student teaching in an urban environment. The research will…

  15. Neural networks for perception human and machine perception

    CERN Document Server

    Wechsler, Harry

    1991-01-01

    Neural Networks for Perception, Volume 1: Human and Machine Perception focuses on models for understanding human perception in terms of distributed computation and examples of PDP models for machine perception. This book addresses both theoretical and practical issues related to the feasibility of both explaining human perception and implementing machine perception in terms of neural network models. The book is organized into two parts. The first part focuses on human perception. Topics on network model ofobject recognition in human vision, the self-organization of functional architecture in t

  16. Linear study and bundle adjustment data fusion; Application to vision localization; Recherche lineaire et fusion de donnees par ajustement de faisceaux; Application a la localisation par vision

    Energy Technology Data Exchange (ETDEWEB)

    Michot, J.

    2010-12-09

    integrate this additional information directly into an extended bundle adjustment, by adding a constraint term in the weighted cost function. We evaluate three methods (based on machine learning or regularization) that dynamically select the weight associated to the constraint and show that these methods can be used in a real time multi-sensor SLAM, and validate them with different types of constraint on the orientation or on the scale. Experiments conducted on real video sequences show that this technique of constrained bundle adjustment reduces the drifts observed with the classical vision algorithms and improves the global accuracy of the positioning system. (author) [French] Les travaux presentes dans ce manuscrit concernent le domaine de la localisation et la reconstruction 3D par vision artificielle. Dans ce contexte, la trajectoire d'une camera et la structure 3D de la scene filmee sont initialement estimees par des algorithmes lineaires puis optimisees par un algorithme non-lineaire, l'ajustement de faisceaux. Cette these presente tout d'abord une technique de recherche de l'amplitude de deplacement (recherche lineaire), ou line search pour les algorithmes de minimisation iterative. La technique proposee est non iterative et peut etre rapidement implantee dans un ajustement de faisceaux traditionnel. Cette technique appelee recherche lineaire algebrique globale (G-ALS), ainsi que sa variante a deux dimensions (Two way-ALS), accelerent la convergence de l'algorithme d'ajustement de faisceaux. L'approximation de l'erreur de reprojection par une distance algebrique rend possible le calcul analytique d'une amplitude de deplacement efficace (ou de deux pour la variante Two way-ALS), par la resolution d'un polynome de degre 3 (G-ALS) ou 5 (Two way-ALS). Nos experimentations sur des donnees simulees et reelles montrent que cette amplitude, optimale en distance algebrique, est performante en distance euclidienne, et permet

  17. Safety Computer Vision Rules for Improved Sensor Certification

    DEFF Research Database (Denmark)

    Mogensen, Johann Thor Ingibergsson; Kraft, Dirk; Schultz, Ulrik Pagh

    2017-01-01

    Mobile robots are used across many domains from personal care to agriculture. Working in dynamic open-ended environments puts high constraints on the robot perception system, which is critical for the safety of the system as a whole. To achieve the required safety levels the perception system needs...... to be certified, but no specific standards exist for computer vision systems, and the concept of safe vision systems remains largely unexplored. In this paper we present a novel domain-specific language that allows the programmer to express image quality detection rules for enforcing safety constraints...

  18. Outdoor Lighting: Physics, Vision and Perception

    CERN Document Server

    Schreuder, Duco

    2008-01-01

    This book covers theoretical aspects that are at the basis of lighting installations. It focuses on insight, backgrounds and coherence. There are many fundamental aspects that are essential for understanding why different ways to install and use lighting give different results. A purely pragmatic approach to solving practical lighting problems will lead to pitfalls. But as this book shows, on the basis of fundamental considerations on optics, light sources and vision, causes and effects that tend to be overlooked by lighting engineers and designers can be identified. The selection of subjects in this book is based on more than 50 years of experience in studying the fundamental and practical applications of lighting and vision. The author has given classes on these topics, in master courses at post-graduate and post-doctoral levels. Audience: graduate students, researchers, designers, engineers and consultants engaged in lighting, public lighting, lighting equipment and installations.

  19. Towards computer-based perception by modeling visual perception : A probalistic theory

    NARCIS (Netherlands)

    Ciftcioglu, O.; Bittermann, M.; Sariyildiz, S.

    2006-01-01

    Studies on computer-based perception by vision modelling are described. The visual perception is mathematically modelled where the model receives and interprets visual data from the environment. The perception is defined in probabilistic terms so that it is in the same way quantified. Human visual

  20. Vision servo of industrial robot: A review

    Science.gov (United States)

    Zhang, Yujin

    2018-04-01

    Robot technology has been implemented to various areas of production and life. With the continuous development of robot applications, requirements of the robot are also getting higher and higher. In order to get better perception of the robots, vision sensors have been widely used in industrial robots. In this paper, application directions of industrial robots are reviewed. The development, classification and application of robot vision servo technology are discussed, and the development prospect of industrial robot vision servo technology is proposed.

  1. An overview of quantitative approaches in Gestalt perception.

    Science.gov (United States)

    Jäkel, Frank; Singh, Manish; Wichmann, Felix A; Herzog, Michael H

    2016-09-01

    Gestalt psychology is often criticized as lacking quantitative measurements and precise mathematical models. While this is true of the early Gestalt school, today there are many quantitative approaches in Gestalt perception and the special issue of Vision Research "Quantitative Approaches in Gestalt Perception" showcases the current state-of-the-art. In this article we give an overview of these current approaches. For example, ideal observer models are one of the standard quantitative tools in vision research and there is a clear trend to try and apply this tool to Gestalt perception and thereby integrate Gestalt perception into mainstream vision research. More generally, Bayesian models, long popular in other areas of vision research, are increasingly being employed to model perceptual grouping as well. Thus, although experimental and theoretical approaches to Gestalt perception remain quite diverse, we are hopeful that these quantitative trends will pave the way for a unified theory. Copyright © 2016 Elsevier Ltd. All rights reserved.

  2. Une éthique de l'adaptation ?

    Directory of Open Access Journals (Sweden)

    Jan Spurk

    2011-10-01

    Full Text Available Jacques Beauchemin présente une argumentation à la fois extrêmement dense et érudite mais aussi très pédagogique pour développer sa vision de « la société des identités », comme il appelle notre monde contemporain, ainsi que les perspectives éthiques et politiques de celle-ci.Les thèses centrales sont clairement indiquées dès la première page (de la préface de la seconde édition de 2005 : sur la base de la « radicalisation de la modernité » (Anthony Giddens, l’inégalité sociale n’est plus p...

  3. From humans to computers cognition through visual perception

    CERN Document Server

    Alexandrov, Viktor Vasilievitch

    1991-01-01

    This book considers computer vision to be an integral part of the artificial intelligence system. The core of the book is an analysis of possible approaches to the creation of artificial vision systems, which simulate human visual perception. Much attention is paid to the latest achievements in visual psychology and physiology, the description of the functional and structural organization of the human perception mechanism, the peculiarities of artistic perception and the expression of reality. Computer vision models based on these data are investigated. They include the processes of external d

  4. Une analyse des représentations des enseignants réfléchissant sur une expérience d’implantation d’un portfolio électronique / An Analysis of the Perceptions of Teachers Reflecting on an Experience of e-Portfolio Implementation

    Directory of Open Access Journals (Sweden)

    Ann-Louise Davidson

    2012-08-01

    Full Text Available Cet article rend compte d’une analyse des représentations avec des enseignants, qui a eu lieu à la fin d’une expérience d’implantation d’un portfolio électronique favorisant l’autorégulation des apprentissages des élèves et la professionnalisation des enseignants. Le texte s’appuie sur le contexte éducatif québécois actuel. Ensuite, il présente une revue de littérature entourant les compétences technologiques, les portfolios électroniques et l’autorégulation des apprentissages. La méthodologie présente le design de la recherche, les instruments utilisés pour les entretiens et pour animer le groupe de discussion. Les résultats montrent que pour une enseignante qui avait déjà adopté la pédagogie sous-jacente au renouveau pédagogique Québécois, le portfolio électronique était une expérience fort utile. Toutefois, pour les deux autres enseignants, l’implantation du portfolio électronique était beaucoup trop exigeante. Finalement, nous discutons des implications des résultats, autant au point de vue de l’expérience d’implantation des portfolios électroniques que du point de vue de la contribution méthodologique. This article presents an analysis of the perceptions of teachers, which took place in 2010 at the end of an experiment implementing an e-portfolio that facilitates student self-regulation of learning. The article is based on the current Quebec educational context. It presents a review of literature on technology skills, e-portfolios and the self-regulation of learning. The methodology describes the research design, the tools used in the individual interviews and in the group discussion. The results indicate that the e-portfolio was a valuable experience for a teacher who had already adopted the pedagogy underlying the education reform in Quebec. However the implementation of the e-portfolio was difficult for the other two teachers due to challenges in terms of technology and managing

  5. Sensory Drive, Color, and Color Vision.

    Science.gov (United States)

    Price, Trevor D

    2017-08-01

    Colors often appear to differ in arbitrary ways among related species. However, a fraction of color diversity may be explained because some signals are more easily perceived in one environment rather than another. Models show that not only signals but also the perception of signals should regularly evolve in response to different environments, whether these primarily involve detection of conspecifics or detection of predators and prey. Thus, a deeper understanding of how perception of color correlates with environmental attributes should help generate more predictive models of color divergence. Here, I briefly review our understanding of color vision in vertebrates. Then I focus on opsin spectral tuning and opsin expression, two traits involved in color perception that have become amenable to study. I ask how opsin tuning is correlated with ecological differences, notably the light environment, and how this potentially affects perception of conspecific colors. Although opsin tuning appears to evolve slowly, opsin expression levels are more evolutionarily labile but have been difficult to connect to color perception. The challenge going forward will be to identify how physiological differences involved in color vision, such as opsin expression levels, translate into perceptual differences, the selection pressures that have driven those differences, and ultimately how this may drive evolution of conspecific colors.

  6. Front-end vision and multi-scale image analysis multi-scale computer vision theory and applications, written in Mathematica

    CERN Document Server

    Romeny, Bart M Haar

    2008-01-01

    Front-End Vision and Multi-Scale Image Analysis is a tutorial in multi-scale methods for computer vision and image processing. It builds on the cross fertilization between human visual perception and multi-scale computer vision (`scale-space') theory and applications. The multi-scale strategies recognized in the first stages of the human visual system are carefully examined, and taken as inspiration for the many geometric methods discussed. All chapters are written in Mathematica, a spectacular high-level language for symbolic and numerical manipulations. The book presents a new and effective

  7. Colour vision experimental studies in teaching of optometry

    Science.gov (United States)

    Ozolinsh, Maris; Ikaunieks, Gatis; Fomins, Sergejs

    2005-10-01

    Following aspects related to human colour vision are included in experimental lessons for optometry students of University of Latvia. Characteristics of coloured stimuli (emitting and reflective), determination their coordinates in different colour spaces. Objective characteristics of transmitting of colour stimuli through the optical system of eye together with various types of appliances (lenses, prisms, Fresnel prisms). Psychophysical determination of mono- and polychromatic stimuli perception taking into account physiology of eye, retinal colour photoreceptor topography and spectral sensitivity, spatial and temporal characteristics of retinal receptive fields. Ergonomics of visual perception, influence of illumination and glare effects, testing of colour vision deficiencies.

  8. Adolescents with Low Vision: Perceptions of Driving and Nondriving

    Science.gov (United States)

    Sacks, Sharon Zell; Rosenblum, L. Penny

    2006-01-01

    Two studies examined how adolescents with low vision perceive their ability to drive. The results of both studies indicated similarities in the participants' responses with respect to knowledge of visual impairment, information about options for driving with low vision, frustrations and obstacles imposed by not being able to drive, and independent…

  9. Experiences of vision impairment in Papua New Guinea: implications for blindness prevention programs.

    Science.gov (United States)

    Burnett, Anthea; Yashadhana, Aryati; Cabrera Aguas, Maria; Hanni, Yvonne; Yu, Mitasha

    2016-01-01

    A person's capability to access services and achieve good eye health is influenced by their behaviours, perceptions, beliefs and experiences. As evidence from Papua New Guinea (PNG) about people's lived experience with vision impairment is limited, the purpose of the present study was to better understand the beliefs, perceptions and emotional responses to vision impairment in PNG. A qualitative study, using both purposive and convenience sampling, was undertaken to explore common beliefs and perceptions about vision impairment, as well as the emotional responses to vision impairment. In-depth interviews were undertaken with 51 adults from five provinces representing culturally and geographically diverse regions of PNG. Grounded theory was used to elicit key themes from interview data. Participants described activities of everyday life impacted by vision impairment and the related worry, sadness and social exclusion. Common beliefs about the causes of vision impairment were environmental stressors (sun, dust, dirt and smoke), ageing and sorcery. Findings provide insight into the unique social context in PNG and identify a number of programmatic and policy implications, such as the need for preventative eye health information and services, addressing persisting beliefs in sorcery when developing health information packages, and the importance of coordinating with counselling and well-being services for people experiencing vision impairment.

  10. Barriers to accessing low vision services.

    Science.gov (United States)

    Pollard, Tamara L; Simpson, John A; Lamoureux, Ecosse L; Keeffe, Jill E

    2003-07-01

    To investigate barriers to accessing low vision services in Australia. Adults with a vision impairment (vision difficulties, duration of vision loss and satisfaction with vision and also examined issues of awareness of low vision services and referral to services. Focus groups were also conducted with vision impaired (Vision Australia Foundation. The discussions were recorded and transcribed. The questionnaire revealed that referral to low vision services was associated with a greater degree of vision loss (p = 0.002) and a greater self-perception of low vision (p = 0.005) but that referral was not associated with satisfaction (p = 0.144) or difficulties related to vision (p = 0.169). Participants with mild and moderate vision impairment each reported similar levels of difficulties with daily activities and satisfaction with their vision (p > 0.05). However, there was a significant difference in the level of difficulties experienced with daily activities between those with mild-moderate and severe vision impairment (p low vision services related to awareness of services among the general public and eye care professionals, understanding of low vision and the services available, acceptance of low vision, the referral process, and transport. In addition to the expected difficulties with lack of awareness of services by people with low vision, many people do not understand what the services provide and do not identify themselves as having low vision. Knowledge of these barriers, from the perspective of people with low vision, can now be used to guide the development and content of future health-promotion campaigns.

  11. 78 FR 12815 - Qualification of Drivers; Exemption Applications; Vision

    Science.gov (United States)

    2013-02-25

    .... The best corrected visual acuity in his right eye is light perception, and in his left eye, 20/20.... Lifelong. Stable. Visual fields WNL. Color WNL. No contraindications for commercial driving.'' Mr. Clark... color vision, 180 degrees of peripheral vision, no medical contraindication to commercial truck driving...

  12. Évaluation de la qualité de la connaissance dans une perspective délibérative

    NARCIS (Netherlands)

    van der Sluijs, J.P.; Douguet, J.M.; O'Connor, M.; Ravetz, J.

    2008-01-01

    sh Cet article propose une vision des démarches d’évaluation de l’adéquation de la connaissance scientifique dans des situations d’incertitude forte et irréductible en recourant à des processus délibératifs élargis. Dans l’optique de la Science Post-Normale, la démarche s’appuie, d’un point de vue

  13. Prospective territoriale en terre de développement durable : une application à la région Guadeloupe Territorial prospective in land of sustainable development : an application to the region Guadeloupe

    Directory of Open Access Journals (Sweden)

    Yvette Lazzeri

    2012-05-01

    Full Text Available La région durable doit se positionner dans un contexte d'ouverture et de concurrence territoriale. À défaut de pouvoir influencer notablement les paramètres du changement global, les acteurs sont appelés à les anticiper et à les prendre en compte dans leurs stratégies. Ils sont invités à élaborer une vision prospective qui renouvelle leurs rapports au territoire dans la perspective du développement durable. C’est dans cet esprit que l’exercice de prospective a été développé. La méthode, présentée ici pour la région Guadeloupe, intègre à la fois les tendances lourdes liées à l’environnement contextuel et les tendances lourdes spécifiques au territoire. Au-delà d’un scénario au fil de l’eau qui peut conduire à une marginalisation de la région, deux visions du devenir guadeloupéen sont analysées vers une inacceptable et une souhaitable.Sustainable Region should position itself in a context of openness and territorial competition. Without the ability to significantly influence the parameters of global change, the actors are called upon to anticipate and take them into account in their strategies. They are encouraged to develop a future vision that renews their relationship to the territory in the context of sustainable development. It is in this spirit that Territorial Prospective exercise was developed. The method presented here for the Guadeloupe region, integrates both trends related to the contextual environment and trends specific to the territory. Beyond a scenario over water which can lead to a marginalization of the region, two visions of the future are analyzed Guadeloupe ... towards one unacceptable and one desirable.

  14. Haptic perception disambiguates visual perception of 3D shape

    NARCIS (Netherlands)

    Wijntjes, Maarten W A; Volcic, Robert; Pont, Sylvia C.; Koenderink, Jan J.; Kappers, Astrid M L

    We studied the influence of haptics on visual perception of three-dimensional shape. Observers were shown pictures of an oblate spheroid in two different orientations. A gauge-figure task was used to measure their perception of the global shape. In the first two sessions only vision was used. The

  15. Soft Computing Techniques in Vision Science

    CERN Document Server

    Yang, Yeon-Mo

    2012-01-01

    This Special Edited Volume is a unique approach towards Computational solution for the upcoming field of study called Vision Science. From a scientific firmament Optics, Ophthalmology, and Optical Science has surpassed an Odyssey of optimizing configurations of Optical systems, Surveillance Cameras and other Nano optical devices with the metaphor of Nano Science and Technology. Still these systems are falling short of its computational aspect to achieve the pinnacle of human vision system. In this edited volume much attention has been given to address the coupling issues Computational Science and Vision Studies.  It is a comprehensive collection of research works addressing various related areas of Vision Science like Visual Perception and Visual system, Cognitive Psychology, Neuroscience, Psychophysics and Ophthalmology, linguistic relativity, color vision etc. This issue carries some latest developments in the form of research articles and presentations. The volume is rich of contents with technical tools ...

  16. Produire des textes descriptifs en allemand L2: Les effets de l’interaction dyadique sur la planification et la révision textuelles dans une classe de 7ème degré

    OpenAIRE

    Jacquin, Marianne

    2004-01-01

    Cet article résume les résultats d’une recherche exploratoire, ayant pour but d’analyser l’effet de l’interaction en dyades sur l’écriture de textes descriptifs en allemand L2. 17 élèves de 7ème année du Cycle d’Orientation de Genève ont rédigé deux textes dans deux conditions différentes: interaction en phase de planification (1) et de révision (2). L’écriture du texte lui-même s’est faite individuellement. Un troisième texte était planifié, rédigé et révisé seul par tous les élèves, afin de...

  17. Artificial vision support system (AVS(2)) for improved prosthetic vision.

    Science.gov (United States)

    Fink, Wolfgang; Tarbell, Mark A

    2014-11-01

    State-of-the-art and upcoming camera-driven, implanted artificial vision systems provide only tens to hundreds of electrodes, affording only limited visual perception for blind subjects. Therefore, real time image processing is crucial to enhance and optimize this limited perception. Since tens or hundreds of pixels/electrodes allow only for a very crude approximation of the typically megapixel optical resolution of the external camera image feed, the preservation and enhancement of contrast differences and transitions, such as edges, are especially important compared to picture details such as object texture. An Artificial Vision Support System (AVS(2)) is devised that displays the captured video stream in a pixelation conforming to the dimension of the epi-retinal implant electrode array. AVS(2), using efficient image processing modules, modifies the captured video stream in real time, enhancing 'present but hidden' objects to overcome inadequacies or extremes in the camera imagery. As a result, visual prosthesis carriers may now be able to discern such objects in their 'field-of-view', thus enabling mobility in environments that would otherwise be too hazardous to navigate. The image processing modules can be engaged repeatedly in a user-defined order, which is a unique capability. AVS(2) is directly applicable to any artificial vision system that is based on an imaging modality (video, infrared, sound, ultrasound, microwave, radar, etc.) as the first step in the stimulation/processing cascade, such as: retinal implants (i.e. epi-retinal, sub-retinal, suprachoroidal), optic nerve implants, cortical implants, electric tongue stimulators, or tactile stimulators.

  18. Embedding visual routines in AnaFocus' Eye-RIS Vision Systems for closing the perception to action loop in roving robots

    Science.gov (United States)

    Jiménez-Marrufo, A.; Caballero-García, D. J.

    2011-05-01

    The purpose of the current paper is to describe how different visual routines can be developed and embedded in the AnaFocus' Eye-RIS Vision System on Chip (VSoC) to close the perception to action loop within the roving robots developed under the framework of SPARK II European project. The Eye-RIS Vision System on Chip employs a bio-inspired architecture where image acquisition and processing are truly intermingled and the processing itself is carried out in two steps. At the first step, processing is fully parallel owing to the concourse of dedicated circuit structures which are integrated close to the sensors. At the second step, processing is realized on digitally-coded information data by means of digital processors. All these capabilities make the Eye-RIS VSoC very suitable for the integration within small robots in general, and within the robots developed by the SPARK II project in particular. These systems provide with image-processing capabilities and speed comparable to high-end conventional vision systems without the need for high-density image memory and intensive digital processing. As far as perception is concerned, current perceptual schemes are often based on information derived from visual routines. Since real world images are quite complex to be processed for perceptual needs with traditional approaches, more computationally feasible algorithms are required to extract the desired features from the scene in real time, to efficiently proceed with the consequent action. In this paper the development of such algorithms and their implementation taking full advantage of the sensing-processing capabilities of the Eye-RIS VSoC are described.

  19. Maxwell: A new vision of the world

    Science.gov (United States)

    Maystre, Daniel

    2014-05-01

    The paper outlines the crucial contributions of James Clerk Maxwell to Physics and more generally to our vision of the world. He achieved 150 years ago a synthesis of the pioneering works in magnetostatics, electrostatics, induction and, by introducing the notion of displacement current, gave birth to Electromagnetics. Then, he deduced the existence of electromagnetic waves and identified light as one of them. Maxwell equations deeply changed a Newtonian conception of the world based on particle interactions by pointing out the vital role of waves in physics. This new conception had a strong influence on the development of quantum physics. Finally, the invariance of light velocity in Galilean frames led to Lorentz transformations, a key step toward the theory of relativity. Par ailleurs, les équations de Maxwell ont profondément changé une conception du monde newtonienne basée sur l'interaction entre particules en révélant le rôle essentiel des ondes en physique, ce qui eut une influence déterminante sur le développement de la physique quantique. Enfin, l'invariance de la vitesse de la lumière dans les repères galiléens a entraîné la découverte des transformations de Lorentz, une étape capitale vers la théorie de la relativité.

  20. Augmentation of Cognition and Perception Through Advanced Synthetic Vision Technology

    Science.gov (United States)

    Prinzel, Lawrence J., III; Kramer, Lynda J.; Bailey, Randall E.; Arthur, Jarvis J.; Williams, Steve P.; McNabb, Jennifer

    2005-01-01

    Synthetic Vision System technology augments reality and creates a virtual visual meteorological condition that extends a pilot's cognitive and perceptual capabilities during flight operations when outside visibility is restricted. The paper describes the NASA Synthetic Vision System for commercial aviation with an emphasis on how the technology achieves Augmented Cognition objectives.

  1. The Culture of the BBC: A Personal Appreciation La culture de la BBC : Une appréciation personnelle

    Directory of Open Access Journals (Sweden)

    Lord Asa Briggs

    2004-01-01

    Full Text Available Cet article entend apporter une vision personnelle et indépendante de l’évolution des valeurs affichées par la BBC depuis sa création en 1922. Les premières années de l’histoire de la BBC ont été influencées par les centres d’intérêt de son fondateur Lord Reith – allégeance à l’Écosse, à la religion presbytérienne, à sa formation d’ingénieur et au souvenir de la Première Guerre mondiale. Par la suite, la BBC n’a plus véhiculé une culture mais des cultures, son monopole sur le discours concernant la culture et la société ayant été remis en question sous l’influence de changements dans la composition de la société dans les années 1960. Dans les années 1980, au moment où se développe la radiodiffusion commerciale, la BBC a résisté à la tentation de considérer son audience comme un marché. La BBC ne peut donc selon Asa Briggs entrer dans les problématiques de l’École de Francfort. Au début du vingt-et-unième siècle, si l’impact de la philosophie de Reith est encore palpable (attachement à la notion de service public, refus du profit comme justification, la hiérarchie des missions de la BBC a changé : alors qu’initialement, la mission de la BBC était régie par une « sainte trinité » où se succédaient dans cet ordre divertissement, éducation et information, cette dernière a maintenant acquis la première place ; l’éducation reçoit une importance nouvelle. En revanche, si l’émission la plus ancienne à la radio britannique était une émission religieuse, la BBC n’affiche plus de mission ni envers la religion, ni envers le sport. La possession de compétences technologiques prime désormais sur l’articulation d’une vision lorsqu’il s’agit de recruter des dirigeants pour cette institution.

  2. Vision under mesopic and scotopic illumination

    Directory of Open Access Journals (Sweden)

    Andrew J Zele

    2015-01-01

    Full Text Available Evidence has accumulated that rod activation under mesopic and scotopic light levels alters visual perception and performance. Here we review the most recent developments in the measurement of rod and cone contributions to mesopic color perception and temporal processing, with a focus on data measured using the four-primary photostimulator method that independently controls rod and cone excitations. We discuss the findings in the context of rod inputs to the three primary retinogeniculate pathways to understand rod contributions to mesopic vision. Additionally, we present evidence that hue perception is possible under scotopic, pure rod-mediated conditions that involves cortical mechanisms.

  3. Pour une vision élargie des performances de la filière ostréicole à partir d’une approche en termes de patrimoine for a broader vision of the performances of the oyster farming industry from an approach in terms of heritage

    Directory of Open Access Journals (Sweden)

    Audrey Rivaud

    2012-05-01

    Full Text Available Dans le but de contribuer aux réflexions relatives à l’élargissement de la notion de performance, nous entendons traiter la question de la performance d’une filière économique dans une perspective située, à la fois dans l’espace et dans le temps, en mettant en lumière la variété des éléments constitutifs de la performance d’une part et l’existence de tensions, voire de contradictions entre ces éléments d’autre part. Dès lors, nous soutenons l’idée d’une diversité de modèles de production performants et insistons sur la nécessité d’identifier des indicateurs adaptés à cette diversité. Nous nous appuyons pour cela sur les outils conceptuels développés dans le cadre de l’économie patrimoniale. Nous illustrons notre propos en nous appuyant sur le cas de la filière ostréicole dans le Bassin d’Arcachon.This article deals with the question of the performance of an industry, viewed in its relations with the space and with the time. The purpose, which contributes to the literature relating to the broadening of the performance, is to insist on the variety of constituent elements of the performance on the one hand and on the existence of contradictions between these elements on the other hand. Thus, we assume the diversity of performing production models and we stress the importance to define indicators which take into account this diversity. To this end, the tools developed within the framework of the heritage economy are used. We refer to the case study of oyster-farming industry in the Arcachon Bay (France to illustrate these points.

  4. Une masse palpébrale révélant une fistule carotidocaverneuse ...

    African Journals Online (AJOL)

    ... huit mois une masse palpébrale droite, avec une discrète exophtalmie et hémorragie sous conjonctivale, l'angio IRM a permis de confirmer le diagnostique d'une fistule carotidocaverneuse à haut débit, qui est responsable de cette symptomatologie. L'objectif de cet article est de mettre la lumière sur cette pathologie rare, ...

  5. Une Nouvelle Orientation Psychophysique dans la Pédagogie Théâtrale Contemporaine

    Directory of Open Access Journals (Sweden)

    Vezio Ruggieri

    2015-09-01

    Full Text Available Cet article a pour but de présenter comment les apports du modèle psychophysiologique bio-existentialiste élaboré par Vezio Ruggieri et ses collaborateurs peuvent jeter une lumière nouvelle sur les processus sous-jacents le jeu de l’acteur tels que la présence scénique, le processus d’identification avec un personnage et le complexe mécanisme de la prosodie. Cet encadrement théorique, qui voit le rapport corps-esprit dans une relation circulaire, éclairera le lecteur sur les bases physiologiques de la perception et de l’imagination ainsi que sur le rôle fondamental que la structure musculaire joue dans la construction de ces phénomènes.

  6. Deep learning: Using machine learning to study biological vision

    OpenAIRE

    Majaj, Najib; Pelli, Denis

    2017-01-01

    Today most vision-science presentations mention machine learning. Many neuroscientists use machine learning to decode neural responses. Many perception scientists try to understand recognition by living organisms. To them, machine learning offers a reference of attainable performance based on learned stimuli. This brief overview of the use of machine learning in biological vision touches on its strengths, weaknesses, milestones, controversies, and current directions.

  7. Optoelectronic vision

    Science.gov (United States)

    Ren, Chunye; Parel, Jean-Marie A.

    1993-06-01

    Scientists have searched every discipline to find effective methods of treating blindness, such as using aids based on conversion of the optical image, to auditory or tactile stimuli. However, the limited performance of such equipment and difficulties in training patients have seriously hampered practical applications. A great edification has been given by the discovery of Foerster (1929) and Krause & Schum (1931), who found that the electrical stimulation of the visual cortex evokes the perception of a small spot of light called `phosphene' in both blind and sighted subjects. According to this principle, it is possible to invite artificial vision by using stimulation with electrodes placed on the vision neural system, thereby developing a prosthesis for the blind that might be of value in reading and mobility. In fact, a number of investigators have already exploited this phenomena to produce a functional visual prosthesis, bringing about great advances in this area.

  8. Colombia, mining country. Vision a year 2019

    International Nuclear Information System (INIS)

    2006-01-01

    Scope of the state action for the mining sector, the performance of the mining sector, regional perceptions of mining development, construction of a long-term vision for the mining sector, the action plan and goals follow-up

  9. Bilateral idiopathic optic perineuritis with severe vision loss: A case report

    Directory of Open Access Journals (Sweden)

    Wee-Min Teh

    2015-07-01

    Full Text Available Optic perineuritis is an orbital inflammatory disorder that is either idiopathic or secondary to other conditions such as infection or systemic inflammatory disorders. This condition is very similar to demyelinating optic neuritis, but certain features of the history and magnetic resonance imaging findings are characteristic for and aid in the diagnosis of optic perineuritis. Vision loss varies greatly, from minimal clouding of vision up to only light perception. We report a case of a 44-year-old female with idiopathic bilateral optic perineuritis with vision loss of up to no light perception in both eyes. Radio imaging studies were typical of optic perineuritis and she was started on systemic corticosteroids. She responded very well to steroid therapy and achieved nearly complete visual recovery. There had been no relapse despite cessation of therapy.

  10. Mechanisms of Percept-Percept and Image-Percept Integration in Vision: Behavioral and Electrophysiological Evidence

    Science.gov (United States)

    Dalvit, Silvia; Eimer, Martin

    2011-01-01

    Previous research has shown that the detection of a visual target can be guided not only by the temporal integration of two percepts, but also by integrating a percept and an image held in working memory. Behavioral and event-related brain potential (ERP) measures were obtained in a target detection task that required temporal integration of 2…

  11. Pour une nouvelle approche de l'hispanité grâce aux TICE - La formation d'enseignants d'espagnol langue étrangère Towards a new approach of Hispanic culture thanks to ICT - Beginners training for Spanish language teachers

    Directory of Open Access Journals (Sweden)

    Veronique Pugibet

    2006-04-01

    Full Text Available Si désormais les divers pays et cultures du monde hispanique figurent dans les programmes officiels de l'apprentissage de l'espagnol langue étrangère en France, l'approche qui en est proposée demeure encore souvent traditionnelle, une certaine vision de l'histoire et les "beaux" textes dominant largement. Comment amener les jeunes enseignants en formation initiale à porter un regard différent sur l'autre, à atteindre une véritable compétence culturelle dépassant la culture académique ? Nous rendrons compte dans notre étude de la spécificité de la formation initiale des professeurs d'espagnol qui, dorénavant, sont de plus en plus nombreux à être d'origine hispanophone. Nous exposerons leur parcours de formation sur et grâce aux TICE afin de dépasser les clichés réducteurs initiaux comme en témoignent leur approche première sur Internet, et en vue d'atteindre un regard plus ouvert sur l'hispanité et des pratiques pédagogiques différentes.Despite the ongoing presence of several Hispanic countries and cultures in state programs concerning Spanish as a foreign language in French education, the suggested methodology remains very often traditional with a predominantly biased vision of history as well as texts that are considered "beautiful". How can we help young teachers in their initial training to have a different perception of the other, to reach a true cultural competence that surpasses academic culture? We will show in our study the details involved in a Spanish teacher's initial training since, as it appears, they tend to be more and more of Hispanic origin. We will describe their training history through and thanks to the TICE in order to overcome the reductive and stereotyping clichés as they move initially towards the use of Internet, and in order to reach out for a more open perception of the Hispanic World and of different pedagogical practices.

  12. Building Artificial Vision Systems with Machine Learning

    Energy Technology Data Exchange (ETDEWEB)

    LeCun, Yann [New York University

    2011-02-23

    Three questions pose the next challenge for Artificial Intelligence (AI), robotics, and neuroscience. How do we learn perception (e.g. vision)? How do we learn representations of the perceptual world? How do we learn visual categories from just a few examples?

  13. Early vision and visual attention

    Directory of Open Access Journals (Sweden)

    Gvozdenović Vasilije P.

    2003-01-01

    Full Text Available The question whether visual perception is spontaneous, sudden or is running through several phases, mediated by higher cognitive processes, was raised ever since the early work of Gestalt psychologists. In the early 1980s, Treisman proposed the feature integration theory of attention (FIT, based on the findings of neuroscience. Soon after publishing her theory a new scientific approach appeared investigating several visual perception phenomena. The most widely researched were the key constructs of FIT, like types of visual search and the role of the attention. The following review describes the main studies of early vision and visual attention.

  14. Predictors of vision impairment in Multiple Sclerosis.

    Science.gov (United States)

    Sanchez-Dalmau, Bernardo; Martinez-Lapiscina, Elena H; Pulido-Valdeolivas, Irene; Zubizarreta, Irati; Llufriu, Sara; Blanco, Yolanda; Sola-Valls, Nuria; Sepulveda, Maria; Guerrero, Ana; Alba, Salut; Andorra, Magi; Camos, Anna; Sanchez-Vela, Laura; Alfonso, Veronica; Saiz, Albert; Villoslada, Pablo

    2018-01-01

    Visual impairment significantly alters the quality of life of people with Multiple Sclerosis (MS). The objective of this study was to identify predictors (independent variables) of visual outcomes, and to define their relationship with neurological disability and retinal atrophy when assessed by optical coherence tomography (OCT). We performed a cross-sectional analysis of 119 consecutive patients with MS, assessing vision using high contrast visual acuity (LogMar), 2.5% and 1.25% low contrast visual acuity (Sloan charts), and color vision (Hardy-Rand-Rittler plates). Quality of vision is a patient reported outcome based on an individual's unique perception of his or her vision and was assessed with the Visual Functioning Questionnaire-25 (VFQ-25) with the 10 neuro-ophthalmologic items. MS disability was assessed using the expanded disability status scale (EDSS), the MS functional composite (MSFC) and the brief repetitive battery-neuropsychology (BRB-N). Retinal atrophy was assessed using spectral domain OCT, measuring the thickness of the peripapillar retinal nerve fiber layer (pRNFL) and the volume of the ganglion cell plus inner plexiform layer (GCIPL). The vision of patients with MS was impaired, particularly in eyes with prior optic neuritis. Retinal atrophy (pRNFL and GCIPL) was closely associated with impaired low contrast vision and color vision, whereas the volume of the GCIPL showed a trend (p = 0.092) to be associated with quality of vision. Multiple regression analysis revealed that EDSS was an explanatory variable for high contrast vision after stepwise analysis, GCIPL volume for low contrast vision, and GCIPL volume and EDSS for color vision. The explanatory variables for quality of vision were high contrast vision and color vision. In summary, quality of vision in MS depends on the impairment of high contrast visual acuity and color vision due to the disease.

  15. Rationality, perception, and the all-seeing eye.

    Science.gov (United States)

    Felin, Teppo; Koenderink, Jan; Krueger, Joachim I

    2017-08-01

    Seeing-perception and vision-is implicitly the fundamental building block of the literature on rationality and cognition. Herbert Simon and Daniel Kahneman's arguments against the omniscience of economic agents-and the concept of bounded rationality-depend critically on a particular view of the nature of perception and vision. We propose that this framework of rationality merely replaces economic omniscience with perceptual omniscience. We show how the cognitive and social sciences feature a pervasive but problematic meta-assumption that is characterized by an "all-seeing eye." We raise concerns about this assumption and discuss different ways in which the all-seeing eye manifests itself in existing research on (bounded) rationality. We first consider the centrality of vision and perception in Simon's pioneering work. We then point to Kahneman's work-particularly his article "Maps of Bounded Rationality"-to illustrate the pervasiveness of an all-seeing view of perception, as manifested in the extensive use of visual examples and illusions. Similar assumptions about perception can be found across a large literature in the cognitive sciences. The central problem is the present emphasis on inverse optics-the objective nature of objects and environments, e.g., size, contrast, and color. This framework ignores the nature of the organism and perceiver. We argue instead that reality is constructed and expressed, and we discuss the species-specificity of perception, as well as perception as a user interface. We draw on vision science as well as the arts to develop an alternative understanding of rationality in the cognitive and social sciences. We conclude with a discussion of the implications of our arguments for the rationality and decision-making literature in cognitive psychology and behavioral economics, along with suggesting some ways forward.

  16. VIP - A Framework-Based Approach to Robot Vision

    Directory of Open Access Journals (Sweden)

    Gerd Mayer

    2008-11-01

    Full Text Available For robot perception, video cameras are very valuable sensors, but the computer vision methods applied to extract information from camera images are usually computationally expensive. Integrating computer vision methods into a robot control architecture requires to balance exploitation of camera images with the need to preserve reactivity and robustness. We claim that better software support is needed in order to facilitate and simplify the application of computer vision and image processing methods on autonomous mobile robots. In particular, such support must address a simplified specification of image processing architectures, control and synchronization issues of image processing steps, and the integration of the image processing machinery into the overall robot control architecture. This paper introduces the video image processing (VIP framework, a software framework for multithreaded control flow modeling in robot vision.

  17. VIP - A Framework-Based Approach to Robot Vision

    Directory of Open Access Journals (Sweden)

    Hans Utz

    2006-03-01

    Full Text Available For robot perception, video cameras are very valuable sensors, but the computer vision methods applied to extract information from camera images are usually computationally expensive. Integrating computer vision methods into a robot control architecture requires to balance exploitation of camera images with the need to preserve reactivity and robustness. We claim that better software support is needed in order to facilitate and simplify the application of computer vision and image processing methods on autonomous mobile robots. In particular, such support must address a simplified specification of image processing architectures, control and synchronization issues of image processing steps, and the integration of the image processing machinery into the overall robot control architecture. This paper introduces the video image processing (VIP framework, a software framework for multithreaded control flow modeling in robot vision.

  18. Functional Dissociation between Perception and Action Is Evident Early in Life

    Science.gov (United States)

    Hadad, Bat-Sheva; Avidan, Galia; Ganel, Tzvi

    2012-01-01

    The functional distinction between vision for perception and vision for action is well documented in the mature visual system. Ganel and colleagues recently provided direct evidence for this dissociation, showing that while visual processing for perception follows Weber's fundamental law of psychophysics, action violates this law. We tracked the…

  19. Méthodologie de conception de motifs dirigée par la distance de Hamming : application à la reconstruction de surfaces à partir d'une seule image

    OpenAIRE

    Maurice , Xavier; Doignon , Christophe

    2012-01-01

    Session "Articles"; National audience; En vision artificielle par lumière structurée, la projection d'un motif sur un objet permet de capturer la forme de sa surface à un instant donné, en effectuant plusieurs acquisitions. Cette technique peut cependant s'avérer inefficace lorsque l'objet est en mouvement. Il devient alors nécessaire de ne faire appel qu'à une seule prise d'images pour analyser la forme d'une région d'intérêt en mouvement et des motifs intégrant des propriétés intrinsèques d...

  20. Perceptions of journalists on women access, employment and participation in news production: A case study of Uganda's print media-The New Vision

    OpenAIRE

    Anyango, Jane

    2009-01-01

    Abstract The thesis, “Perceptions of journalists on women access, employment and participation in news production” constitutes an assessment of the situation of female journalists in one of Uganda’s print media, The New Vision. The study connects the problematic relationship that women have with news media, both as subjects and sources of news stories as well as their experiences and status as practitioners within the news industries. The study was concerned over what in this profession...

  1. Deleuze, Bergson, Bachelard et Bazin,les ambigüités entre phénoménologie et sémiotique pour une théorie du temps filmique

    Directory of Open Access Journals (Sweden)

    Lenice Pereira Barbosa

    2013-12-01

    Full Text Available Ce texte est né de la nécessité de structurer théoriquement ce qui, selon une approche empirique, est une évidence : aborder les considérations d’André Bazin et de Gilles Deleuze concernant le temps cinématographique à travers un point de vue phénoménologique. Ceci pourrait, bien évidemment, entrainer un « chassé-croisé » théorique entre Sémiotique et Phénoménologie qui se neutraliseraient les unes les autres sans apporter de changements par rapport à la perception chromatique du temps. L’objectif principal de ce travail est d’élargir le sens attribué à l’élément couleur au cinéma et de mettre en exergue le rapport entre les manifestations chromatiques et la perception du temps. À partir de ces points, il est également possible de considérer le principe multi – disciplinaire que ces éléments nous imposent, inspiré par l’évidence de la continuité-discontinuité qui, en tout cas au cinéma, n’est pas nécessairement un dilemme. Ainsi, il s’agit de faire coexister dans une approche phénoménologique certaines conceptions de Bergson et de Bachelard concernant la perception du temps.

  2. An information assistant system for the prevention of tunnel vision in crisis management

    NARCIS (Netherlands)

    Cao, Y.

    2008-01-01

    In the crisis management environment, tunnel vision is a set of bias in decision makers’ cognitive process which often leads to incorrect understanding of the real crisis situation, biased perception of information, and improper decisions. The tunnel vision phenomenon is a consequence of both the

  3. FLORA™: Phase I development of a functional vision assessment for prosthetic vision users.

    Science.gov (United States)

    Geruschat, Duane R; Flax, Marshall; Tanna, Nilima; Bianchi, Michelle; Fisher, Andy; Goldschmidt, Mira; Fisher, Lynne; Dagnelie, Gislin; Deremeik, Jim; Smith, Audrey; Anaflous, Fatima; Dorn, Jessy

    2015-07-01

    Research groups and funding agencies need a functional assessment suitable for an ultra-low vision population to evaluate the impact of new vision-restoration treatments. The purpose of this study was to develop a pilot assessment to capture the functional visual ability and well-being of subjects whose vision has been partially restored with the Argus II Retinal Prosthesis System. The Functional Low-Vision Observer Rated Assessment (FLORA) pilot assessment involved a self-report section, a list of functional visual tasks for observation of performance and a case narrative summary. Results were analysed to determine whether the interview questions and functional visual tasks were appropriate for this ultra-low vision population and whether the ratings suffered from floor or ceiling effects. Thirty subjects with severe to profound retinitis pigmentosa (bare light perception or worse in both eyes) were enrolled in a clinical trial and implanted with the Argus II System. From this population, 26 subjects were assessed with the FLORA. Seven different evaluators administered the assessment. All 14 interview questions were asked. All 35 tasks for functional vision were selected for evaluation at least once, with an average of 20 subjects being evaluated for each test item. All four rating options—impossible (33 per cent), difficult (23 per cent), moderate (24 per cent) and easy (19 per cent)—were used by the evaluators. Evaluators also judged the amount of vision they observed the subjects using to complete the various tasks, with 'vision only' occurring 75 per cent on average with the System ON, and 29 per cent with the System OFF. The first version of the FLORA was found to contain useful elements for evaluation and to avoid floor and ceiling effects. The next phase of development will be to refine the assessment and to establish reliability and validity to increase its value as an assessment tool for functional vision and well-being. © 2015 The Authors. Clinical

  4. Soins primaires aux adultes ayant une déficience développementale

    Science.gov (United States)

    Sullivan, William F.; Berg, Joseph M.; Bradley, Elspeth; Cheetham, Tom; Denton, Richard; Heng, John; Hennen, Brian; Joyce, David; Kelly, Maureen; Korossy, Marika; Lunsky, Yona; McMillan, Shirley

    2011-01-01

    Résumé Objectif Mettre à jour les lignes directrices canadiennes de 2006 sur les soins primaires aux adultes ayant une déficience développementale (DD) et présenter des recommandations pratiques fondées sur les connaissances actuelles pour traiter des problèmes de santé particuliers chez des adultes ayant une DD. Qualité des preuves Des professionnels de la santé expérimentés participant à un colloque et un groupe de travail subséquent ont discuté et convenu des révisions aux lignes directrices de 2006 en se fondant sur une recherche documentaire exhaustive, la rétroaction obtenue des utilisateurs du guide de pratique et les expériences cliniques personnelles. La plupart des preuves disponibles dans ce domaine viennent de l’opinion d’experts ou de déclarations consensuelles publiées (niveau III). Message principal Les adultes ayant une DD ont des problèmes de santé complexes, dont plusieurs diffèrent de ceux de la population en général. De bons soins primaires permettent d’identifier les problèmes de santé particuliers dont souffrent les adultes ayant une DD pour améliorer leur qualité de vie et leur accès aux soins de santé et prévenir la morbidité et le décès prématuré. Ces lignes directrices résument les problèmes de santé générale, physique, comportementale et mentale des adultes ayant une DD que devraient connaître les professionnels des soins primaires et présentent des recommandations pour le dépistage et la prise en charge en se basant sur les connaissances actuelles que les cliniciens peuvent mettre en pratique. En raison de l’interaction des facteurs biologiques, psychoaffectifs et sociaux qui contribuent à la santé et au bien-être des adultes ayant une DD, ces lignes directrices insistent sur la participation des aidants, l’adaptation des interventions, au besoin, et la consultation auprès de divers professionnels de la santé quand ils sont accessibles. Elles mettent aussi en évidence la

  5. Une hanche douloureuse révélatrice d'une histiocytose osseuse multifocale

    Science.gov (United States)

    Lahrach, Kamal; Alaoui, Adil; el Kadi, Khalid Ibn; Marzouki, Amine; Boutayeb, Fawzi

    2014-01-01

    L'histiocytose langerhansienne est une maladie rare qui touche principalement l'enfant et l'adulte jeune. Elle peut prendre plusieurs aspects, L'atteinte osseuse peut être uni- ou multifocale. Nous rapportons une observation d'histiocytose langerhansienne osseuse multifocale, révélée chez un patient âgé de 23 ans et ayant touché le col fémoral droit. La scintigraphie osseuse a permis de retrouver plusieurs localisations: l'os temporal, humérale et scapulaire droite. En raison du risque fracturaire, le patient a bénéficié d'une ostéosynthèse par vis-plaque DHS avec curetage biopsie de la lésion. L'examen histologique a révélé une histiocytose langerhansienne. L'évolution fut favorable après chimiothérapie par voie générale. PMID:25018840

  6. Self-powered vision electronic-skin basing on piezo-photodetecting Ppy/PVDF pixel-patterned matrix for mimicking vision

    Science.gov (United States)

    Han, Wuxiao; Zhang, Linlin; He, Haoxuan; Liu, Hongmin; Xing, Lili; Xue, Xinyu

    2018-06-01

    The development of multifunctional electronic-skin that establishes human-machine interfaces, enhances perception abilities or has other distinct biomedical applications is the key to the realization of artificial intelligence. In this paper, a new self-powered (battery-free) flexible vision electronic-skin has been realized from pixel-patterned matrix of piezo-photodetecting PVDF/Ppy film. The electronic-skin under applied deformation can actively output piezoelectric voltage, and the outputting signal can be significantly influenced by UV illumination. The piezoelectric output can act as both the photodetecting signal and electricity power. The reliability is demonstrated over 200 light on–off cycles. The sensing unit matrix of 6 × 6 pixels on the electronic-skin can realize image recognition through mapping multi-point UV stimuli. This self-powered vision electronic-skin that simply mimics human retina may have potential application in vision substitution.

  7. Self-powered vision electronic-skin basing on piezo-photodetecting Ppy/PVDF pixel-patterned matrix for mimicking vision.

    Science.gov (United States)

    Han, Wuxiao; Zhang, Linlin; He, Haoxuan; Liu, Hongmin; Xing, Lili; Xue, Xinyu

    2018-06-22

    The development of multifunctional electronic-skin that establishes human-machine interfaces, enhances perception abilities or has other distinct biomedical applications is the key to the realization of artificial intelligence. In this paper, a new self-powered (battery-free) flexible vision electronic-skin has been realized from pixel-patterned matrix of piezo-photodetecting PVDF/Ppy film. The electronic-skin under applied deformation can actively output piezoelectric voltage, and the outputting signal can be significantly influenced by UV illumination. The piezoelectric output can act as both the photodetecting signal and electricity power. The reliability is demonstrated over 200 light on-off cycles. The sensing unit matrix of 6 × 6 pixels on the electronic-skin can realize image recognition through mapping multi-point UV stimuli. This self-powered vision electronic-skin that simply mimics human retina may have potential application in vision substitution.

  8. LA DIVERSITÉ DÉPLOYÉE AU SEIN DE L’UNIVERSITÉ D’ENTREPRISE : L’APPLICATION CONCRÈTE D’UNE VALEUR ADOPTÉE PAR LA DIRECTION GÉNÉRALE

    Directory of Open Access Journals (Sweden)

    Virginia Drummond-Guitel

    2009-09-01

    Full Text Available La diversité devenue une valeur incontournable adoptée par les grands groupes, encore faut-t-il trouver les moyens concrets pour l’intégrer dans les pratiques des ressources humaines et dans les mentalités des personnes. Le présent papier a pour but de montrer comment les valeurs de la diversité adoptées par la direction générale ont été déclinées et appliquées dans un processus de sélection de candidats pour une formation continue au sein d’une grande organisation internationale. A travers l’application d’une méthode qualitative de recherche, 10 (dix dirigeants ayant conçu la formation et 42 (quarante-deux managers ayant suivi le programme confirment l’atteinte du but stratégique de cette formation, autrement dit, l’atteinte d’une vision partagée (SENGE, 1991, à travers la consolidation d’un fort sentiment d’appartenance à la culture organisationnelle (SCHEIN, 1995. Les managers ont été sélectionnés selon leurs différentes professions, cultures nationales et différents secteurs d’activités, confirmant ainsi une promotion de la diversité au sein de l’organisation.

  9. LATE VISION: PROCESSES AND EPISTEMIC STATUS

    Directory of Open Access Journals (Sweden)

    Athanassios eRaftopoulos

    2011-12-01

    Full Text Available In this paper, I examine the processes that occur in late vision and address the problem of whether late vision should be construed as a properly speaking perceptual stage, or as a thought-like discursive stage. Specifically, I argue that late vision, its (partly conceptual nature notwithstanding, neither is constituted by nor does it implicate what I call pure thoughts, that is, propositional structures that are formed in the cognitive areas of the brain through, and participate in, discursive reasoning and inferences. At the same time, the output of late vision, namely an explicit belief concerning the identity and category membership of an object (that is, a recognitional belief or its features, eventually enters into discursive reasoning. Using Jackendoff’s distinction between visual awareness, which characterizes perception, and visual understanding, which characterizes pure thought, I claim that the contents of late vision belong to visual awareness and not to visual understanding and that although late vision implicates beliefs, either implicit or explicit, these beliefs are hybrid visual/conceptual constructs and not pure thoughts. Distinguishing between these hybrid representations and pure thoughts and delineating the nature of the representations of late vision lays the ground for examining, among other things, the process of conceptualization that occurs in visual processing and the way concepts modulate perceptual content affecting either its representational or phenomenal character. I also do not discuss the epistemological relations between the representations of late vision and the perceptual judgments they ‘support’, or ‘guide’ or ‘render possible’ or ‘evidence’ or ‘entitle’. However, the specification of the epistemology of late vision lays the ground for attacking that problem as well.

  10. Early vision and focal attention

    Science.gov (United States)

    Julesz, Bela

    1991-07-01

    At the thirty-year anniversary of the introduction of the technique of computer-generated random-dot stereograms and random-dot cinematograms into psychology, the impact of the technique on brain research and on the study of artificial intelligence is reviewed. The main finding-that stereoscopic depth perception (stereopsis), motion perception, and preattentive texture discrimination are basically bottom-up processes, which occur without the help of the top-down processes of cognition and semantic memory-greatly simplifies the study of these processes of early vision and permits the linking of human perception with monkey neurophysiology. Particularly interesting are the unexpected findings that stereopsis (assumed to be local) is a global process, while texture discrimination (assumed to be a global process, governed by statistics) is local, based on some conspicuous local features (textons). It is shown that the top-down process of "shape (depth) from shading" does not affect stereopsis, and some of the models of machine vision are evaluated. The asymmetry effect of human texture discrimination is discussed, together with recent nonlinear spatial filter models and a novel extension of the texton theory that can cope with the asymmetry problem. This didactic review attempts to introduce the physicist to the field of psychobiology and its problems-including metascientific problems of brain research, problems of scientific creativity, the state of artificial intelligence research (including connectionist neural networks) aimed at modeling brain activity, and the fundamental role of focal attention in mental events.

  11. Henri Lopès : d’Une Quête Incessante à une identité plurielle

    Directory of Open Access Journals (Sweden)

    Vincent Simédoh

    2006-04-01

    Full Text Available Dans plusieurs oeuvres d’Henri Lopès, les personnages sont constamment en quête d’une identité. Une quête qu’ils entament comme un parcours puisque désormais ils vivent au confluent de plusieurs cultures et ils se sentent comme en exil. Ce n’est pas forcément un exil extérieur parce qu’ils ont quitté leur pays d’origine mais c’est plutôt un exil intérieur. Ainsi les personnages se sentent incapables de se situer par rapport à eux-mêmes et à autrui. Dès lors surgit une tentation, celle de se réfugier dans le souvenir qui n’existe même plus. La mémoire s’estompe. L’histoire elle-même fuit et disparaît. Ce qui fait naître chez les personnages un vide qui conduit à un malaise identitaire, d’où déchirement. En face de cet écartèlement, surgit une multitude de pistes. Et c’est dans cette perspective qu’Henri Lopès propose une identité plurielle.

  12. Impact d'une modulation duale sur les performances d'une liaison ...

    African Journals Online (AJOL)

    Le présent document présente la technique de modulation duale Fréquence - Amplitude dans le cas d'une liaison optique du type IM-DD. Ce travail révèle que la modulation duale Fréquence - Amplitude permet de générer un signal à bande latérale unique. Les performances d'une liaison optique IM-DD basée sur cette ...

  13. Uma abordagem de geomarketing do esporte Une approche géomarketing du sport

    Directory of Open Access Journals (Sweden)

    Loïc Ravenel

    2011-07-01

    idée de la seule représentation spatiale de données pour l’intégration de la dimension géographique dans la stratégie marketing. Cette intégration nous pousse vers une vision plus systémique utilisant le marketing comme un modèle d’analyse des services sportifs, services pour lesquels les choix des pratiquants ou consommateurs sont devenus prépondérants. Après avoir replacé les recherches en géographie des sports dans leur contexte scientifique, une définition du géomarketing est proposée, insistant sur la spécificité des services sportifs. Trois grands domaines d’interventions sont ensuite identifiés comme des pistes de travail qui combinent les attentes des acteurs avec de nouvelles perspectives géographiques.This article presents, from a conceptual and functional point of view, the contribution of a geomarketing for the analysis of the sport. Beyond of collusion between geography and marketing, it firstly implies an operational decisional phase for the progression of the sports activity. If its methods borrow much from the space analysis and geomatics, and fall under a structuralist prospect, the interest of the geomarketing should not be limited to the market research, nor to the cartography of the customers or prospective customers within the market radiuses: we wish to go from the mere vision of data representation going towards an integration of geographical dimension into the marketing strategy. This integration leads us towards a more systemic vision, using marketing as a model of analysis of the sporting services, for which the choices of the practitioners or consumers become dominating. After having replaced sports geography research in their scientific context, a definition of geomarketing is proposed, insisting on the specificity of the sporting services. Three great fields of interventions are then identified as of the working tracks which combine expectations of the actors with geographical new prospects.

  14. Modulation frequency as a cue for auditory speed perception.

    Science.gov (United States)

    Senna, Irene; Parise, Cesare V; Ernst, Marc O

    2017-07-12

    Unlike vision, the mechanisms underlying auditory motion perception are poorly understood. Here we describe an auditory motion illusion revealing a novel cue to auditory speed perception: the temporal frequency of amplitude modulation (AM-frequency), typical for rattling sounds. Naturally, corrugated objects sliding across each other generate rattling sounds whose AM-frequency tends to directly correlate with speed. We found that AM-frequency modulates auditory speed perception in a highly systematic fashion: moving sounds with higher AM-frequency are perceived as moving faster than sounds with lower AM-frequency. Even more interestingly, sounds with higher AM-frequency also induce stronger motion aftereffects. This reveals the existence of specialized neural mechanisms for auditory motion perception, which are sensitive to AM-frequency. Thus, in spatial hearing, the brain successfully capitalizes on the AM-frequency of rattling sounds to estimate the speed of moving objects. This tightly parallels previous findings in motion vision, where spatio-temporal frequency of moving displays systematically affects both speed perception and the magnitude of the motion aftereffects. Such an analogy with vision suggests that motion detection may rely on canonical computations, with similar neural mechanisms shared across the different modalities. © 2017 The Author(s).

  15. Emotion-Induced Trade-Offs in Spatiotemporal Vision

    Science.gov (United States)

    Bocanegra, Bruno R.; Zeelenberg, Rene

    2011-01-01

    It is generally assumed that emotion facilitates human vision in order to promote adaptive responses to a potential threat in the environment. Surprisingly, we recently found that emotion in some cases impairs the perception of elementary visual features (Bocanegra & Zeelenberg, 2009b). Here, we demonstrate that emotion improves fast temporal…

  16. Bio-inspired vision

    International Nuclear Information System (INIS)

    Posch, C

    2012-01-01

    Nature still outperforms the most powerful computers in routine functions involving perception, sensing and actuation like vision, audition, and motion control, and is, most strikingly, orders of magnitude more energy-efficient than its artificial competitors. The reasons for the superior performance of biological systems are subject to diverse investigations, but it is clear that the form of hardware and the style of computation in nervous systems are fundamentally different from what is used in artificial synchronous information processing systems. Very generally speaking, biological neural systems rely on a large number of relatively simple, slow and unreliable processing elements and obtain performance and robustness from a massively parallel principle of operation and a high level of redundancy where the failure of single elements usually does not induce any observable system performance degradation. In the late 1980's, Carver Mead demonstrated that silicon VLSI technology can be employed in implementing ''neuromorphic'' circuits that mimic neural functions and fabricating building blocks that work like their biological role models. Neuromorphic systems, as the biological systems they model, are adaptive, fault-tolerant and scalable, and process information using energy-efficient, asynchronous, event-driven methods. In this paper, some basics of neuromorphic electronic engineering and its impact on recent developments in optical sensing and artificial vision are presented. It is demonstrated that bio-inspired vision systems have the potential to outperform conventional, frame-based vision acquisition and processing systems in many application fields and to establish new benchmarks in terms of redundancy suppression/data compression, dynamic range, temporal resolution and power efficiency to realize advanced functionality like 3D vision, object tracking, motor control, visual feedback loops, etc. in real-time. It is argued that future artificial vision systems

  17. Sensorimotor Interactions in the Haptic Perception of Virtual Objects

    Science.gov (United States)

    1997-01-01

    the human user. 2 Compared to our understanding of vision and audition , our knowledge of the human haptic perception is very limited. Many basic...modalities such as vision and audition on haptic perception of viscosity or mass, for example. 116 Some preliminary work has already been done in this...string[3]; *posx="x" *forf="f’ *velv="v" * acca ="a" trial[64]; resp[64]; /* random number */ /* trial number */ /* index */ /* array holding stim

  18. 76 FR 37883 - Qualification of Drivers; Exemption Applications; Vision

    Science.gov (United States)

    2011-06-28

    ... your comments, please include a self-addressed, stamped envelope or postcard or print the..., including amblyopia, complete loss of vision, no light perception, cataract, central retinal atrophy...). Other studies demonstrated theories of predicting crash proneness from crash history coupled with other...

  19. Brain mechanisms for simple perception and bistable perception.

    Science.gov (United States)

    Wang, Megan; Arteaga, Daniel; He, Biyu J

    2013-08-27

    When faced with ambiguous sensory inputs, subjective perception alternates between the different interpretations in a stochastic manner. Such multistable perception phenomena have intrigued scientists and laymen alike for over a century. Despite rigorous investigations, the underlying mechanisms of multistable perception remain elusive. Recent studies using multivariate pattern analysis revealed that activity patterns in posterior visual areas correlate with fluctuating percepts. However, increasing evidence suggests that vision--and perception at large--is an active inferential process involving hierarchical brain systems. We applied searchlight multivariate pattern analysis to functional magnetic resonance imaging signals across the human brain to decode perceptual content during bistable perception and simple unambiguous perception. Although perceptually reflective activity patterns during simple perception localized predominantly to posterior visual regions, bistable perception involved additionally many higher-order frontoparietal and temporal regions. Moreover, compared with simple perception, both top-down and bottom-up influences were dramatically enhanced during bistable perception. We further studied the intermittent presentation of ambiguous images--a condition that is known to elicit perceptual memory. Compared with continuous presentation, intermittent presentation recruited even more higher-order regions and was accompanied by further strengthened top-down influences but relatively weakened bottom-up influences. Taken together, these results strongly support an active top-down inferential process in perception.

  20. Functional vision loss: a diagnosis of exclusion.

    Science.gov (United States)

    Villegas, Rex B; Ilsen, Pauline F

    2007-10-01

    Most cases of visual acuity or visual field loss can be attributed to ocular pathology or ocular manifestations of systemic pathology. They can also occasionally be attributed to nonpathologic processes or malingering. Functional vision loss is any decrease in vision the origin of which cannot be attributed to a pathologic or structural abnormality. Two cases of functional vision loss are described. In the first, a 58-year-old man presented for a baseline eye examination for enrollment in a vision rehabilitation program. He reported bilateral blindness since a motor vehicle accident with head trauma 4 years prior. Entering visual acuity was "no light perception" in each eye. Ocular health examination was normal and the patient made frequent eye contact with the examiners. He was referred for neuroimaging and electrophysiologic testing. The second case was a 49-year-old man who presented with a long history of intermittent monocular diplopia. His medical history was significant for psycho-medical evaluations and a diagnosis of factitious disorder. Entering uncorrected visual acuities were 20/20 in each eye, but visual field testing found constriction. No abnormalities were found that could account for the monocular diplopia or visual field deficit. A diagnosis of functional vision loss secondary to factitious disorder was made. Functional vision loss is a diagnosis of exclusion. In the event of reduced vision in the context of a normal ocular health examination, all other pathology must be ruled out before making the diagnosis of functional vision loss. Evaluation must include auxiliary ophthalmologic testing, neuroimaging of the visual pathway, review of the medical history and lifestyle, and psychiatric evaluation. Comanagement with a psychiatrist is essential for patients with functional vision loss.

  1. Coevolution of coloration and colour vision?

    Science.gov (United States)

    Lind, Olle; Henze, Miriam J; Kelber, Almut; Osorio, Daniel

    2017-07-05

    The evolutionary relationship between signals and animal senses has broad significance, with potential consequences for speciation, and for the efficacy and honesty of biological communication. Here we outline current understanding of the diversity of colour vision in two contrasting groups: the phylogenetically conservative birds, and the more variable butterflies. Evidence for coevolution of colour signals and vision exists in both groups, but is limited to observations of phenotypic differences between visual systems, which might be correlated with coloration. Here, to illustrate how one might interpret the evolutionary significance of such differences, we used colour vision modelling based on an avian eye to evaluate the effects of variation in three key characters: photoreceptor spectral sensitivity, oil droplet pigmentation and the proportions of different photoreceptor types. The models predict that physiologically realistic changes in any one character will have little effect, but complementary shifts in all three can substantially affect discriminability of three types of natural spectra. These observations about the adaptive landscape of colour vision may help to explain the general conservatism of photoreceptor spectral sensitivities in birds. This approach can be extended to other types of eye and spectra to inform future work on coevolution of coloration and colour vision.This article is part of the themed issue 'Animal coloration: production, perception, function and application'. © 2017 The Author(s).

  2. Declarative Rule-based Safety for Robotic Perception Systems

    DEFF Research Database (Denmark)

    Mogensen, Johann Thor Ingibergsson; Kraft, Dirk; Schultz, Ulrik Pagh

    2017-01-01

    Mobile robots are used across many domains from personal care to agriculture. Working in dynamic open-ended environments puts high constraints on the robot perception system, which is critical for the safety of the system as a whole. To achieve the required safety levels the perception system needs...... to be certified, but no specific standards exist for computer vision systems, and the concept of safe vision systems remains largely unexplored. In this paper we present a novel domain-specific language that allows the programmer to express image quality detection rules for enforcing safety constraints...

  3. L'allocation universelle, une solution d'avenir?

    OpenAIRE

    Van Parijs, Philippe

    2012-01-01

    Le fait L’avenir de la sécurité sociale fait aussi débat en Suisse. Une initiative populaire vient d’être lancée “pour un revenu de base inconditionnel”. Si elle récolte 100000 signatures, cette proposition pourra être soumise à une votation pour devenir loi. Plus fort, une “initiative citoyenne européenne” sur cette question va être lancée en septembre. Objectif: un million de signatures. De quoi parle-t-on? Il s’agit d’une allocation universelle attribuée à toute personne individuellement, ...

  4. Arthropathie destructrice des epaules au cours d�une acromegalie

    Directory of Open Access Journals (Sweden)

    Nessrine Akasbi

    2011-10-01

    Full Text Available L�acromegalie est une maladie endocrinienne rare, en rapport avec une hypersecretion d�hormone de croissance. Elle a des consequences rhumatologiques: l�arthropathie peripherique, l�atteinte rachidienne et les syndromes canalaires. L�atteinte articulaire accompagne une acromegalie active, sa survenue apres un traitement radical et une remission complete est rare. Nous presentons le cas d�une patiente de 70 ans ayant un antecedent d�acromegalie sur adenome hypophysaire il y a 25 ans, traitee chirurgicalement et declaree en remission complete, a developpe une arthropathie destructrice des deux epaules. Le but de notre observation est de mettre le point sur la possibilite d�une atteinte articulaire au cours de l�acromegalie et de son retentissement fonctionnelle.

  5. changing perceptions of discipline and corporal punishment

    African Journals Online (AJOL)

    punishment and, secondly, their perceptions of their disciplinary techniques since ... research on teachers' (un)changing perceptions with regard to the practice of corporal punishment for classroom discipline in order to achieve the vision of quality ...... teaching and classroom management with the aim of enhancing teacher ...

  6. Visual Perception with Color for Architectural Aesthetics

    NARCIS (Netherlands)

    Bittermann, M.S.; Ciftcioglu, O.

    2016-01-01

    Studies on computer-based visual perception and aesthetical judgment for architectural design are presented. In the model, both color and the geometric aspects of human vision are jointly taken into account, quantifying the perception of an individual object, as well as a scene consisting of several

  7. A Symbiosis Between Instructional Systems Design and Project Management / Une symbiose de la conception de matériel pédagogique et de la gestion de projet

    Directory of Open Access Journals (Sweden)

    Cheng-Chang (Sam Pan

    2012-02-01

    Full Text Available This study is intended to explore a complementary relationship between instructional systems design (ISD and project management in an attempt to build a plausible case for integrating project management as a distinct course in the core of the graduate instructional systems design programs. It is argued that ISD and project management should form a symbiosis from a curriculum perspective, in a hope for the prepared instructional designers to create values for customers. An integrated view of ISD and project management is proposed, using three concepts of project management as a reasonable bridge for the integration. Challenges for the proposed view in this position paper are also stated. Cette étude explore la complémentarité de la conception de matériel pédagogique et de la gestion de projets en vue de justifier l’intégration de la gestion de projets à titre de cours distinct au cœur des programmes des cycles supérieurs en conception de matériel pédagogique. L’étude fait valoir l’intérêt d’une symbiose de la conception de matériel pédagogique et de la gestion de projets du point de vue du programme d’études, afin de préparer les concepteurs pédagogiques formés à créer une plus-value pour les clients. Elle propose une vision intégrée de la conception de matériel pédagogique et de la gestion de projets fondée sur trois concepts de la gestion de projets favorisant une telle intégration. Les défis de la vision proposée dans cet exposé de position sont également énoncés.

  8. The Technological Consolidation of UNED in Spain

    Directory of Open Access Journals (Sweden)

    Lorenzo Garcia Aretio

    2001-07-01

    Full Text Available This article discusses the role of the technologies that have been utilized to advance distance teaching and learning by the National Distance Education University (Universidad Nacional de Educación a Distancia – UNED of Spain. Following a description of UNED's historical development and organizational structure, UNED's experience with various educational media is discussed. Printed teaching materials, in the form of didactic units, were one of the first methods to be utilized when UNED began its operations in 1972. In turn, the role of radio and audio recordings, television and video recordings, telephone, videoconferencing, computer systems and computer-mediated communications are also described. UNED's pioneering projects, including the virtual classroom, virtual campus, and a program for the physically handicapped, are also detailed. Recent experiments include providing access to radio and television programs on the Internet and adoption of WebCT. On the horizon for UNED are portals for cellular phones using WAP technology and gearing up for multiple applications in accordance with Universal Mobile Telecommunications Technology (UMTS.

  9. Quality of vision in refractive and cataract surgery, indirect measurers: review article.

    Science.gov (United States)

    Parede, Taís Renata Ribeira; Torricelli, André Augusto Miranda; Mukai, Adriana; Vieira Netto, Marcelo; Bechara, Samir Jacob

    2013-01-01

    Visual acuity is the measurement of an individual's ability to recognize details of an object in a space. Visual function measurements in clinical ophthalmology are limited by factors such as maximum contrast and so it might not adequately reflect the real vision conditions at that moment as well as the subjective aspects of the world perception by the patient. The objective of a successful vision-restoring surgery lies not only in gaining visual acuity lines, but also in vision quality. Therefore, refractive and cataract surgeries have the responsibility of achieving quality results. It is difficult to define quality of vision by a single parameter, and the main functional-vision tests are: contrast sensitivity, disability glare, intraocular stray light and aberrometry. In the current review the different components of the visual function are explained and the several available methods to assess the vision quality are described.

  10. Le syndrome d’Usher: à propos d’une observation

    OpenAIRE

    Daoudi, Chama; boutimzine, Noureddine; Haouzi, Samia El; Lezrek, Omar; Tachfouti, Samira; Lezrek, Mounir; Laghmari, Mina; Daoudi, Rajae

    2017-01-01

    Résumé Le syndrome d'Usher est une maladie génétique comportant une double atteinte sensorielle (auditive et visuelle) appelée surdicécité. Nous rapportons l'observation d'un patient de 50 ans, issue d'un mariage consanguin présentant une surdité congénitale avec une fonction vestibulaire normale et une rétinopathie pigmentaire responsable d'une baisse bilatérale de l'acuité visuelle apparue vers l'âge de 16 ans. Cette association compose le type 2 du syndrome d'Usher, affection rare de trans...

  11. L’éthique narrative selon Paul Ricoeur : une passerelle entre l’éthique spinoziste et les éthiques du care

    Directory of Open Access Journals (Sweden)

    Éric Delassus

    2015-09-01

    Full Text Available Selon Fabienne Brugère, un point de rencontre existe entre l’éthique spinoziste et les éthiques du care, le care pouvant être envisagé comme une réactualisation du conatus spinoziste. Cet article vise à démontrer que cette convergence peut s’établir à partir d’une éthique narrative inspirée de la pensée de Paul Ricoeur. Cela concerne principalement la perception que l’on peut avoir de soi en tant que corps et esprit, dans la mesure où l’esprit est défini par Baruch Spinoza comme « idée du corps ». L’éthique spinoziste invite à se rendre utile aux autres pour augmenter notre puissance d’être et nous libérer d’une servitude qui n’est pas sans rapport avec la vulnérabilité telle que définie dans les éthiques du care. L’humain.e vulnérable a besoin pour se sentir exister d’avoir une idée cohérente de son corps, et le récit est l’une des voies lui permettant de progresser dans cette direction. Encore faut-il, pour y parvenir, trouver des pourvoyeuses et pourvoyeurs de care disposé.e.s à écouter, aptes à susciter en soi le désir de se raconter.

  12. Visions and visioning in foresight activities

    DEFF Research Database (Denmark)

    Jørgensen, Michael Søgaard; Grosu, Dan

    2007-01-01

    The paper discusses the roles of visioning processes and visions in foresight activities and in societal discourses and changes parallel to or following foresight activities. The overall topic can be characterised as the dynamics and mechanisms that make visions and visioning processes work...... or not work. The theoretical part of the paper presents an actor-network theory approach to the analyses of visions and visioning processes, where the shaping of the visions and the visioning and what has made them work or not work is analysed. The empirical part is based on analyses of the roles of visions...... and visioning processes in a number of foresight processes from different societal contexts. The analyses have been carried out as part of the work in the COST A22 network on foresight. A vision is here understood as a description of a desirable or preferable future, compared to a scenario which is understood...

  13. Mise en place d'une base de données pour une modélisation ...

    African Journals Online (AJOL)

    Mise en place d'une base de données pour une modélisation hydrologique distribuée du bassin versant du Bandama (Côte d'Ivoire) : apport d'un modèle numérique d'altitude, de la télédétection et du SIG Physitel.

  14. Virtual Attendance: Analysis of an Audiovisual over IP System for Distance Learning in the Spanish Open University (UNED

    Directory of Open Access Journals (Sweden)

    Esteban Vázquez-Cano

    2013-07-01

    Full Text Available This article analyzes a system of virtual attendance, called “AVIP” (AudioVisual over Internet Protocol, at the Spanish Open University (UNED in Spain. UNED, the largest open university in Europe, is the pioneer in distance education in Spain. It currently has more than 300,000 students, 1,300 teachers, and 6,000 tutors all over the world, besides Spain. This university is redefining, on the lines of other universities, many of its academic processes to meet the new requirements of the European Higher Education Area (EHEA. Since its inception, more than 30 years ago, the methodology chosen by UNED has been blended learning. Today, this university combines face-to-face tutorial sessions with new methodological proposals, mediated by ICT. Through a quantitative methodology, the perception of students and tutors of the new model of virtual tutoring, called AVIP Classrooms, was analyzed. The results show that the new model greatly improves the orientation and teaching methodology of tutors. However, it requires training and new approaches to provide a more collaborative and participatory environment for students.

  15. Vers une signature spatiale de la vulnérabilité épidémiologique en France : l'exemple de la grippe

    Directory of Open Access Journals (Sweden)

    Martine Tabeaud

    2010-10-01

    Full Text Available L'épidémiologie des maladies infectieuses est au cœur des préoccupations de nombreuses instances de santé publique. Plus que jamais d'actualité, cette thématique fut réactivée par les angoisses générées par le syndrome respiratoire aigu sévère (SRAS ou plus récemment par les craintes d'une pandémie grippale issue d'une souche aviaire. Les recherches actuelles concernent aussi les épidémies "banales", telles que les grippes saisonnières, génératrices de situations de crise qu'une meilleure compréhension permettrait de scénariser pour mieux les gérer et pour en tirer des leçons transférables ensuite à des menaces de plus grande ampleur.La géographie a pris part très tôt au débat sur les maladies, mais l'évolution de ses techniques n'a permis que récemment d'entrevoir son opérabilité dans le champ de l'épidémiologie descriptive. C'est en croisant sa vision du risque avec les techniques d'analyse spatiale que la géographie peut proposer une territorialisation des facteurs de vulnérabilité à la grippe : une spatialisation d'un risque sanitaire.The epidemiology of infectious diseases is in the heart of the concerns of numerous authorities of Public health. This theme was reactivated by the anguishes generated by the Severe Acute Respiratory Syndrome (SARS or more recently by the fears of a flu-like pandemic stemming from an avian origin. The current researches also concern "common" epidemics such as the seasonal flu, generating crisis situations. A better understanding would allow to manage them better and to pull them transferable lessons then in bigger scale threats.The geography took part very early in the debate about diseases but the evolution of its techniques allowed only recently glimpsing its operability in the field of the descriptive epidemiology. While crossing the vision of the risk with the techniques of spatial analysis, the geography can propose a territorialization of the vulnerability factors

  16. Binocular combination in abnormal binocular vision.

    Science.gov (United States)

    Ding, Jian; Klein, Stanley A; Levi, Dennis M

    2013-02-08

    We investigated suprathreshold binocular combination in humans with abnormal binocular visual experience early in life. In the first experiment we presented the two eyes with equal but opposite phase shifted sine waves and measured the perceived phase of the cyclopean sine wave. Normal observers have balanced vision between the two eyes when the two eyes' images have equal contrast (i.e., both eyes contribute equally to the perceived image and perceived phase = 0°). However, in observers with strabismus and/or amblyopia, balanced vision requires a higher contrast image in the nondominant eye (NDE) than the dominant eye (DE). This asymmetry between the two eyes is larger than predicted from the contrast sensitivities or monocular perceived contrast of the two eyes and is dependent on contrast and spatial frequency: more asymmetric with higher contrast and/or spatial frequency. Our results also revealed a surprising NDE-to-DE enhancement in some of our abnormal observers. This enhancement is not evident in normal vision because it is normally masked by interocular suppression. However, in these abnormal observers the NDE-to-DE suppression was weak or absent. In the second experiment, we used the identical stimuli to measure the perceived contrast of a cyclopean grating by matching the binocular combined contrast to a standard contrast presented to the DE. These measures provide strong constraints for model fitting. We found asymmetric interocular interactions in binocular contrast perception, which was dependent on both contrast and spatial frequency in the same way as in phase perception. By introducing asymmetric parameters to the modified Ding-Sperling model including interocular contrast gain enhancement, we succeeded in accounting for both binocular combined phase and contrast simultaneously. Adding binocular contrast gain control to the modified Ding-Sperling model enabled us to predict the results of dichoptic and binocular contrast discrimination experiments

  17. Visual function and color vision in adults with Attention-Deficit/Hyperactivity Disorder.

    Science.gov (United States)

    Kim, Soyeon; Chen, Samantha; Tannock, Rosemary

    2014-01-01

    Color vision and self-reported visual function in everyday life in young adults with Attention-Deficit/Hyperactivity Disorder (ADHD) were investigated. Participants were 30 young adults with ADHD and 30 controls matched for age and gender. They were tested individually and completed the Visual Activities Questionnaire (VAQ), Farnsworth-Munsell 100 Hue Test (FMT) and A Quick Test of Cognitive Speed (AQT). The ADHD group reported significantly more problems in 4 of 8 areas on the VAQ: depth perception, peripheral vision, visual search and visual processing speed. Further analyses of VAQ items revealed that the ADHD group endorsed more visual problems associated with driving than controls. Color perception difficulties on the FMT were restricted to the blue spectrum in the ADHD group. FMT and AQT results revealed slower processing of visual stimuli in the ADHD group. A comprehensive investigation of mechanisms underlying visual function and color vision in adults with ADHD is warranted, along with the potential impact of these visual problems on driving performance. Copyright © 2013 Spanish General Council of Optometry. Published by Elsevier Espana. All rights reserved.

  18. Relationship between Vision and Visual Perception in Hong Kong Preschoolers.

    Science.gov (United States)

    Ho, Wing-Cheung; Tang, Minny Mei-Miu; Fu, Ching-Wah; Leung, Ka-Yan; Pang, Peter Chi-Kong; Cheong, Allen Ming-Yan

    2015-05-01

    Although superior performance in visual motor and visual perceptual skills of preschool children has been documented in the Chinese population, a normative database is only available for the US population. This study aimed to determine the normative values for these visuomotor and visual perceptual tests for preschool children in the Hong Kong Chinese population and to investigate the effect of fundamental visual functions on visuomotor and visual perceptual skills. One hundred seventy-four children from six different kindergartens in Hong Kong were recruited. Distance visual acuity, near visual acuity, and stereopsis were tested, along with two measures of visual perception (VP): Visual-Motor Integration (VMI) and Test of Visual-Perceptual Skills (TVPS). Raw VMI and TVPS scores were converted into standard/scaled scores. The impact of basic visual functions on VP (VMI and TVPS) was examined using multiple regression. Visual functions were generally good: only 9.2 and 4.6% of subjects had unilateral and bilateral reduced habitual vision, respectively (distance visual acuity in the better eye >0.3 logMAR [logarithm of the minimum angle of resolution]). Performance in the VMI and in the visual memory and spatial relationships subtests of the TVPS exceeded that reported for age-matched children from the United States. Multiple regression analysis provided evidence that age had the strongest predictive value for the VMI and VP skills. In addition, near visual acuity was weakly associated with performance in the VMI and the visual discrimination and spatial relationships subtests of the TVPS, accounting for a limited proportion of the intersubject variability (R memory/spatial relationships of TVPS subtests, perhaps attributed to greater exposure to such material during their preschool home education. This study provided normality data for VMI and four subtests of the TVPS for Hong Kong Chinese preschool children as a reference for future studies.

  19. [Studies of vision by Leonardo da Vinci].

    Science.gov (United States)

    Berggren, L

    2001-01-01

    Leonardo was an advocate of the intromission theory of vision. Light rays from the object to the eye caused visual perceptions which were transported to the brain ventricles via a hollow optic nerve. Leonardo introduced wax injections to explore the ventricular system. Perceptions were assumed to go to the "senso comune" in the middle (3rd) ventricle, also the seat of the soul. The processing station "imprensiva" in the anterior lateral horns together with memory "memoria" in th posterior (4th) ventricle integrated the visual perceptions to visual experience. - Leonardo's sketches with circular lenses in the center of the eye reveal that his dependence on medieval optics prevailed over anatomical observations. Drawings of the anatomy of the sectioned eye are missing although Leonardo had invented a new embedding technique. In order to dissect the eye without spilling its contents, the eye was first boiled in egg white and then cut. The procedure was now repeated and showed that the ovoid lens after boiling had become spherical. - Leonardo described that light rays were refracted and reflected in the eye but his imperfect anatomy prevented a development of physiological optics. He was, however, the first to compare the eye with a pin-hole camera (camera obscura). Leonardo's drawings of the inverted pictures on the back wall of a camera obscura inspired to its use as an instrument for artistic practice. The camera obscura was for centuries a model for explaining human vision.

  20. Oculocutaneous albinism: identifying and overcoming barriers to vision care in a Nigerian population.

    Science.gov (United States)

    Udeh, N N; Eze, B I; Onwubiko, S N; Arinze, O C; Onwasigwe, E N; Umeh, R E

    2014-06-01

    To assess eye care service utilization, and identify access barriers in a south-eastern Nigerian albino population. The study was a population-based, cross-sectional survey conducted in Enugu state between August, 2011 and January, 2012. Using the data base of the state's Albino Foundation and tailored awareness creation, persons living with albinism were identified and recruited at two study centres. Data on participants' socio-demographics, perception of vision, visual needs, previous eye examination and or low vision assessment, use of glasses or low vision devices were collected. Reasons for non-utilisation of available vision care services were also obtained. Descriptive and comparative statistics were performed. A p low vision assessment and none--0.0% had used low vision device. Of the participants, 82.4% reported previous eye examination, 33.3% had not used spectacles previously, despite the existing need. Ignorance--88.9% and poor access--8.5% were the main barriers to uptake of vision care services. In Enugu, Nigeria, there is poor awareness and low utilization of vision care services among people with albinism. The identified barriers to vision care access are amenable to awareness creation and logistic change in the provision of appropriate vision care services.

  1. Xanthomatose normolipidemique a localisation nasale chez une ...

    African Journals Online (AJOL)

    Introduction : Exposer un cas de xanthomatose normolipidémique. Observation : il s'agit d'une adolescente de 18 ans qui a présenté une masse des cavités nasales dont le bilan paraclinique a plaidé en faveur d'un xanthogranulome juvénile. L'évolution à court terme a été satisfaisante après l'exérèse chirurgicale par une ...

  2. Dense range map reconstruction from a versatile robotic sensor system with an active trinocular vision and a passive binocular vision.

    Science.gov (United States)

    Kim, Min Young; Lee, Hyunkee; Cho, Hyungsuck

    2008-04-10

    One major research issue associated with 3D perception by robotic systems is the creation of efficient sensor systems that can generate dense range maps reliably. A visual sensor system for robotic applications is developed that is inherently equipped with two types of sensor, an active trinocular vision and a passive stereo vision. Unlike in conventional active vision systems that use a large number of images with variations of projected patterns for dense range map acquisition or from conventional passive vision systems that work well on specific environments with sufficient feature information, a cooperative bidirectional sensor fusion method for this visual sensor system enables us to acquire a reliable dense range map using active and passive information simultaneously. The fusion algorithms are composed of two parts, one in which the passive stereo vision helps active vision and the other in which the active trinocular vision helps the passive one. The first part matches the laser patterns in stereo laser images with the help of intensity images; the second part utilizes an information fusion technique using the dynamic programming method in which image regions between laser patterns are matched pixel-by-pixel with help of the fusion results obtained in the first part. To determine how the proposed sensor system and fusion algorithms can work in real applications, the sensor system is implemented on a robotic system, and the proposed algorithms are applied. A series of experimental tests is performed for a variety of configurations of robot and environments. The performance of the sensor system is discussed in detail.

  3. Migration d'une broche dans le canal médullaire cervical après une ...

    African Journals Online (AJOL)

    Migration d'une broche dans le canal médullaire cervical après une ostéosynthèse de l'articulation acromio-claviculaire. Bah Aliou, El Alaoui Adil. Abstract. We report the case of a 49 year-old right-handed chef with left shoulder trauma occurred during a football game. The diagnosis was fracture of the distal quarter of ...

  4. Perceptual organization in computer vision - A review and a proposal for a classificatory structure

    Science.gov (United States)

    Sarkar, Sudeep; Boyer, Kim L.

    1993-01-01

    The evolution of perceptual organization in biological vision, and its necessity in advanced computer vision systems, arises from the characteristic that perception, the extraction of meaning from sensory input, is an intelligent process. This is particularly so for high order organisms and, analogically, for more sophisticated computational models. The role of perceptual organization in computer vision systems is explored. This is done from four vantage points. First, a brief history of perceptual organization research in both humans and computer vision is offered. Next, a classificatory structure in which to cast perceptual organization research to clarify both the nomenclature and the relationships among the many contributions is proposed. Thirdly, the perceptual organization work in computer vision in the context of this classificatory structure is reviewed. Finally, the array of computational techniques applied to perceptual organization problems in computer vision is surveyed.

  5. UNE APPROCHE REGULATIONNISTE DE LA ...

    African Journals Online (AJOL)

    Administrateur

    en ressources naturelles ont enregistré des performances économiques, moins bonnes par .... de gestion», à financer des augmentations de salaires; augmentations qui, très ... entreprises), dans la mesure où, d'une façon générale, elle introduit une plus .... Outre le contrôle strict de la création monétaire, un autre élément.

  6. The Active Pupil: Pupil size in attention, working memory, and active vision

    OpenAIRE

    Mathôt, Sebastiaan

    2015-01-01

    Slides for the following talk: Mathôt, S. (2015, June). The Active Pupil: Pupil Size in Attention, Working Memory, and Active Vision. Talk presented at the Laboratoire de Psychologie de la Perception, Paris, France.

  7. Revisiting the Lissajous figure as a tool to study bistable perception.

    Science.gov (United States)

    Weilnhammer, V A; Ludwig, K; Sterzer, P; Hesselmann, G

    2014-05-01

    During bistable vision perception spontaneously "switches" between two mutually exclusive percepts despite constant sensory input. The endogenous nature of these perceptual transitions has motivated extensive research aimed at the underlying mechanisms, since spontaneous perceptual transitions of bistable stimuli should in principle allow for a dissociation of processes related to sensory stimulation from those related to conscious perception. However, transitions from one conscious percept to another are often not instantaneous, and participants usually report a considerable amount of mixed or unclear percepts. This feature of bistable vision makes it difficult to isolate transition-related visual processes. Here, we revisited an ambiguous depth-from-motion stimulus which was first introduced to experimental psychology more than 80 years ago. This rotating Lissajous figure might prove useful in complementing other bistable stimuli, since its perceptual transitions only occur at critical stimulus configurations and are virtually instantaneous, thus facilitating the construction of a perceptually equivalent replay condition. We found that three parameters of the Lissajous figure - complexity, line width, and rotational speed - differentially modulated its perceptual dominance durations and transition probabilities, thus providing experimenters with a versatile tool to study the perceptual dynamics of bistable vision. Copyright © 2014 Elsevier B.V. All rights reserved.

  8. Colour-grapheme synaesthesia affects binocular vision

    Directory of Open Access Journals (Sweden)

    Chris L.E. Paffen

    2011-11-01

    Full Text Available In colour-grapheme synaesthesia, non-coloured graphemes are perceived as being inherently coloured. In recent years, it has become evident that synaesthesia-inducing graphemes can affect visual processing in a manner comparable to real, physical colours. Here, we exploit the phenomenon of binocular rivalry in which incompatible images presented dichoptically compete for conscious expression. Importantly, the competition only arises if the two images are sufficiently different; if the difference between the images is small, the images will fuse into a single mixed percept. We show that achromatic graphemes that induce synaesthetic colour percepts evoke binocular rivalry, while without the synaesthetic percept, they do not. That is, compared to achromatically perceived graphemes, synaesthesia-inducing graphemes increase the predominance of binocular rivalry over binocular fusion. This finding shows that the synaesthetic colour experience can provide the conditions for evoking binocular rivalry, much like stimulus features that induce rivalry in normal vision.

  9. D'une ouverture de la voyelle /epsilon/ en finale absolue en francais quebecois : analyse acoustique et perceptive

    Science.gov (United States)

    Riverin-Coutlee, Josiane

    Cette contribution est consacree a l'ouverture du /epsilon/ en finale absolue, un phenomene phonetique repute etre en declin en francais quebecois et caracteristique de locuteurs âges, peu scolarises, issus de milieux populaires et s'exprimant en situation de communication informelle. Une analyse acoustique de 480 voyelles /epsilon/ issues de la parole formelle de 40 jeunes etudiants universitaires originaires des centres urbains de Saguenay et de Quebec revele toutefois que le phenomene est encore bien vivant en francais quebecois et qu'il est plus frequent chez les locuteurs de Saguenay, une tendance validee auditivement par accord inter-juges. Les resultats d'un test de discrimination et d'identification mene aupres de 26 etudiants universitaires originaires de ces deux memes villes indiquent que les auditeurs naifs de Saguenay semblent moins sensibles a la variation et moins enclins a juger de l'origine geographique d'un locuteur a partir de sa prononciation de la voyelle /epsilon/ en fin de mot.

  10. Sense creative! The impact of global and local vision, hearing, touching, tasting, and smelling on creative and analytic thought

    NARCIS (Netherlands)

    Förster, J.; Denzler, M.

    2012-01-01

    Holistic (global) versus elemental (local) perception reflects a prominent distinction in psychology; however, so far it has almost entirely been examined in the domain of vision. Current work suggests that global/local processing styles operate across sensory modalities. As for vision, it is

  11. LA DIVERSITÃ DÃPLOYÃE AU SEIN DE LâUNIVERSITÃ DâENTREPRISE : LâAPPLICATION CONCRÃTE DâUNE VALEUR ADOPTÃE PAR LA DIRECTION GÃNÃRALE

    Directory of Open Access Journals (Sweden)

    Virginia Drummond-Guitel

    2009-09-01

    Full Text Available La diversité devenue une valeur incontournable adoptée par les grands groupes, encore faut-t-il trouver les moyens concrets pour lâintégrer dans les pratiques des ressources humaines et dans les mentalités des personnes. Le présent papier a pour but de montrer comment les valeurs de la diversité adoptées par la direction générale ont été déclinées et appliquées dans un processus de sélection de candidats pour une formation continue au sein dâune grande organisation internationale. A travers lâapplication dâune méthode qualitative de recherche, 10 (dix dirigeants ayant conçu la formation et 42 (quarante-deux managers ayant suivi le programme confirment lâatteinte du but stratégique de cette formation, autrement dit, lâatteinte dâune vision partagée (SENGE, 1991, à travers la consolidation dâun fort sentiment dâappartenance à la culture organisationnelle (SCHEIN, 1995. Les managers ont été sélectionnés selon leurs différentes professions, cultures nationales et différents secteurs dâactivités, confirmant ainsi une promotion de la diversité au sein de lâorganisation.

  12. Prediction under Uncertainty on a Mature Field Prévision de production sous incertitude pour un champ mature

    Directory of Open Access Journals (Sweden)

    Feraille M.

    2012-04-01

    uses Gaussian process modeling and an adaptive design strategy. In the final step of the workflow, parametric response surfaces are used to approximate the reservoir production forecasts and obtain their probabilistic distribution by propagating the remaining posterior uncertainty of input parameters. Dans le cadre de l’ingénierie de réservoir, des simulateurs permettent de comprendre et prédire le déplacement des fluides dans le réservoir et ainsi d’optimiser son exploitation. Ces simulateurs prennent en entrée un grand nombre de paramètres qui peuvent être entachés d’incertitudes. Afin d’assurer une production future correcte, la comparaison des différents scénarios d’exploitation possibles doit tenir compte de ces incertitudes. Les prévisions de production ne doivent pas être évaluées en ne considérant qu’un seul cas « moyen » pour chaque scénario mais en intégrant l’incertitude sur les paramètres d’entrée. Dans le cadre de champ mature où un historique de production est disponible, le formalisme Bayésien est bien adapté pour répondre au problème des prédictions sous incertitudes. En effet, il permet de définir les incertitudes, dites a posteriori, sur les entrées du modèle de réservoir en prenant en compte à la fois les données statiques et dynamiques. Ces incertitudes a posteriori peuvent ensuite être propagées afin de calculer des prévisions de production probabilistes pour chaque scénario, tout en respectant la connaissance statique et dynamique du réservoir. Mais l’obtention des incertitudes a posteriori ainsi que la propagation de celles-ci sur les prévisions de production nécessitent un nombre souvent prohibitif de simulations du modèle réservoir. Dans cet article, nous proposons une application de plusieurs techniques statistiques avancées afin de prendre en compte les incertitudes dans les prévisions de production pour un champ mature et ce en utilisant un nombre raisonnable de simulations. Le

  13. Monitor, a Vibrotactile Aid for Environmental Perception: A Field Evaluation by Four People with Severe Hearing and Vision Impairment

    Directory of Open Access Journals (Sweden)

    Parivash Ranjbar

    2013-01-01

    Full Text Available Monitor is a portable vibrotactile aid to improve the ability of people with severe hearing impairment or deafblindness to detect, identify, and recognize the direction of sound-producing events. It transforms and adapts sounds to the frequency sensitivity range of the skin. The aid was evaluated in the field. Four females (44–54 years with Usher Syndrome I (three with tunnel vision and one with only light perception tested the aid at home and in traffic in three different field studies: without Monitor, with Monitor with an omnidirectional microphone, and with Monitor with a directional microphone. The tests were video-documented, and the two field studies with Monitor were initiated after five weeks of training. The detection scores with omnidirectional and directional microphones were 100% for three participants and above 57% for one, both in their home and traffic environments. In the home environment the identification scores with the omnidirectional microphone were 70%–97% and 58%–95% with the directional microphone. The corresponding values in traffic were 29%–100% and 65%–100%, respectively. Their direction perception was improved to some extent by both microphones. Monitor improved the ability of people with deafblindness to detect, identify, and recognize the direction of events producing sounds.

  14. Monitor, a vibrotactile aid for environmental perception: a field evaluation by four people with severe hearing and vision impairment.

    Science.gov (United States)

    Ranjbar, Parivash; Stenström, Ingeborg

    2013-01-01

    Monitor is a portable vibrotactile aid to improve the ability of people with severe hearing impairment or deafblindness to detect, identify, and recognize the direction of sound-producing events. It transforms and adapts sounds to the frequency sensitivity range of the skin. The aid was evaluated in the field. Four females (44-54 years) with Usher Syndrome I (three with tunnel vision and one with only light perception) tested the aid at home and in traffic in three different field studies: without Monitor, with Monitor with an omnidirectional microphone, and with Monitor with a directional microphone. The tests were video-documented, and the two field studies with Monitor were initiated after five weeks of training. The detection scores with omnidirectional and directional microphones were 100% for three participants and above 57% for one, both in their home and traffic environments. In the home environment the identification scores with the omnidirectional microphone were 70%-97% and 58%-95% with the directional microphone. The corresponding values in traffic were 29%-100% and 65%-100%, respectively. Their direction perception was improved to some extent by both microphones. Monitor improved the ability of people with deafblindness to detect, identify, and recognize the direction of events producing sounds.

  15. Une restauration « spectaculaire »

    Directory of Open Access Journals (Sweden)

    Muriel Verbeeck-Boutin

    2010-04-01

    Full Text Available Cet article replace dans le contexte d’une époque la restauration d’une Vierge à l’enfant par Joseph Van der Veken. Documentée par le commanditaire, l’intervention ne répondit pas à son attente et déboucha sur une dérestauration. Ce fait, loin d’être anecdotique, témoigne d’une mutation des mentalités et des sensibilités dans la première moitié du vingtième siècle, et de l’émergence d’une nouvelle conception de la restauration.This article replaces the restoration of a Madonna and Child by Joseph Van der Vecken within the context of a period.Documented by the patron, the intervention did not meet his expectations and resulted in a de-restoration. This fact, far from being anecdotic, is proof of the change in mentalities and sensitivities in the first half of the twentieth century and of the emergence of a new concept of restoration

  16. Collisions entre véhicules et animaux en liberté : état des lieux à partir d'une enquête au sein de la police

    OpenAIRE

    Lehaire, François; Morelle, Kevin; Lejeune, Philippe

    2013-01-01

    Les accidents de la route impliquant des animaux sauvages sont de plus en plus nombreux. En se basant sur les données recueillies par les zones de police en Wallonie, il est possible d’avoir une vision plus claire de la problématique. Dans le cas du cerf et du sanglier, il apparaît clairement que la hausse des accidents est liée à l’augmentation de leurs populations.

  17. New development in robot vision

    CERN Document Server

    Behal, Aman; Chung, Chi-Kit

    2015-01-01

    The field of robotic vision has advanced dramatically recently with the development of new range sensors.  Tremendous progress has been made resulting in significant impact on areas such as robotic navigation, scene/environment understanding, and visual learning. This edited book provides a solid and diversified reference source for some of the most recent important advancements in the field of robotic vision. The book starts with articles that describe new techniques to understand scenes from 2D/3D data such as estimation of planar structures, recognition of multiple objects in the scene using different kinds of features as well as their spatial and semantic relationships, generation of 3D object models, approach to recognize partially occluded objects, etc. Novel techniques are introduced to improve 3D perception accuracy with other sensors such as a gyroscope, positioning accuracy with a visual servoing based alignment strategy for microassembly, and increasing object recognition reliability using related...

  18. Ostéo arthrite tuberculeuse de la cheville et spondylodiscite: une ...

    African Journals Online (AJOL)

    La TDM et l'IRM rachidienne (A, B, C, D) ont montré: une collection épidurale en regard de D3D4D5D6, une destruction vertébrale de D4 avec recul du mur postérieur responsable d'une déformation dorsale avec compression médullaire, une atteinte D8D9D10D11D12 avec présence d'une collection intra-osseuse, une ...

  19. Restauration et traduction : une question de philosophie

    Directory of Open Access Journals (Sweden)

    Pierre Leveau

    2011-05-01

    Full Text Available On peut faire de la restauration une mission de service public, ou une entreprise privée soumise à la loi du marché. Quel sens donner à cette activité ? Philosophiquement, la méthodologie est à réinventer. L’auteur propose pour cela de définir la restauration comme une traduction, c’est-à-dire une transmission en même temps qu’une transaction. Il formule cette hypothèse en engageant un dialogue entre le réalisme et le constructionnalisme.The conservation can be viewed as a public service and also as an economical activity. How to understand such a pratice ? From a philosophical standpoint, this question is methologically challenging. The author claims that conservation can be defined as a translation, i.e. as a transmission and a transaction. He tests this hypothesis through a confrontation between realism and constructionism.

  20. Comparing sports vision among three groups of soft tennis adolescent athletes: Normal vision, refractive errors with and without correction

    Directory of Open Access Journals (Sweden)

    Shih-Tsun Chang

    2015-01-01

    Full Text Available Background: The effect of correcting static vision on sports vision is still not clear. Aim: To examine whether sports vision (depth perception [DP], dynamic visual acuity [DVA], eye movement [EM], peripheral vision [PV], and momentary vision [MV], were different among soft tennis adolescent athletes with normal vision (Group A, with refractive error and corrected with (Group B and without eyeglasses (Group C. Setting and Design: A cross-section study was conducted. Soft tennis athletes aged 10–13 who played softball tennis for 2–5 years, and who were without any ocular diseases and without visual training for the past 3 months were recruited. Materials and Methods: DPs were measured in an absolute deviation (mm between a moving rod and fixing rod (approaching at 25 mm/s, receding at 25 mm/s, approaching at 50 mm/s, receding at 50 mm/s using electric DP tester. A smaller deviation represented better DP. DVA, EM, PV, and MV were measured on a scale from 1 (worse to 10 (best using ATHLEVISION software. Statistical Analysis: Chi-square test and Kruskal–Wallis test was used to compare the data among the three study groups. Results: A total of 73 athletes (37 in Group A, 8 in Group B, 28 in Group C were enrolled in this study. All four items of DP showed significant difference among the three study groups (P = 0.0051, 0.0004, 0.0095, 0.0021. PV displayed significant difference among the three study groups (P = 0.0044. There was no significant difference in DVA, EM, and MV among the three study groups. Conclusions: Significant better DP and PV were seen among soft tennis adolescent athletes with normal vision than those with refractive error regardless whether they had eyeglasses corrected. On the other hand, DVA, EM, and MV were similar among the three study groups.

  1. Quand la biopsie cutanee peut etiqueter une epilepsie

    Directory of Open Access Journals (Sweden)

    Taoufiq Harmouch

    2011-10-01

    Full Text Available La maladie de Lafora (ML represente une forme rare et grave d�epilepsie myoclonique progressive. C�est une affection a transmission autosomique recessive, heterogene sur le plan genetique. Nous rapportons le cas d�une adolescente de 16 ans, issue de parents consanguins de premier degre, qui presente depuis l�age de 14 ans des crises d�epilepsie et des myoclonies. L'examen neurologique a montre un syndrome cerebelleux et une deterioration intellectuelle. La biopsie cutanee etait indispensable pour orienter le diagnostic. La ML a un pronostic constamment fatal. L�etude histologique confirme le diagnostic et l�etude moleculaire peut aider a etablir un conseil genetique.

  2. Perception des risques liés aux changements climatiques dans les ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    4 sept. 2014 ... L'équipe du projet Perception du risque et vulnérabilité des milieux humides sur la côte atlantique de l'Amérique du Sud, qui a commencé en 2012, privilégie une démarche de gestion intégrée des zones côtières et s'appuie sur les perceptions que les parties prenantes ont des risques liés aux ...

  3. Tunnel vision: sharper gradient of spatial attention in autism.

    Science.gov (United States)

    Robertson, Caroline E; Kravitz, Dwight J; Freyberg, Jan; Baron-Cohen, Simon; Baker, Chris I

    2013-04-17

    Enhanced perception of detail has long been regarded a hallmark of autism spectrum conditions (ASC), but its origins are unknown. Normal sensitivity on all fundamental perceptual measures-visual acuity, contrast discrimination, and flicker detection-is strongly established in the literature. If individuals with ASC do not have superior low-level vision, how is perception of detail enhanced? We argue that this apparent paradox can be resolved by considering visual attention, which is known to enhance basic visual sensitivity, resulting in greater acuity and lower contrast thresholds. Here, we demonstrate that the focus of attention and concomitant enhancement of perception are sharper in human individuals with ASC than in matched controls. Using a simple visual acuity task embedded in a standard cueing paradigm, we mapped the spatial and temporal gradients of attentional enhancement by varying the distance and onset time of visual targets relative to an exogenous cue, which obligatorily captures attention. Individuals with ASC demonstrated a greater fall-off in performance with distance from the cue than controls, indicating a sharper spatial gradient of attention. Further, this sharpness was highly correlated with the severity of autistic symptoms in ASC, as well as autistic traits across both ASC and control groups. These findings establish the presence of a form of "tunnel vision" in ASC, with far-reaching implications for our understanding of the social and neurobiological aspects of autism.

  4. Insuffler une énergie nouvelle : donner une voix et une visibilité aux ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    22 oct. 2010 ... J'ai accepté, car cette méthode nous permettait de tenir une véritable consultation auprès des jeunes du Brésil. CRDI – Pouvez-vous nous expliquer en quoi consiste cette méthode ? Grzybowski – Les sondages d'opinion sont importants, mais c'est un peu comme si on tâtait le pouls d'un patient. De même ...

  5. Relationship between upper extremity kinesthetic sense and writing performance by students with low vision.

    Science.gov (United States)

    Aki, Esra; Atasavun, Songül; Kayihan, Holya

    2008-06-01

    Kinesthetic sense plays an important role in writing. Children with low vision lack sensory input from the environment given their loss of vision. This study assessed the effect of upper extremity kinesthetic sense on writing function in two groups, one of students with low vision (9 girls and 11 boys, 9.4 +/- 1.9 yr. of age) and one of sighted students (10 girls and 10 boys, 10.1 +/- 1.3 yr. of age). All participants were given the Kinesthesia Test and Jebsen Hand Function Test-Writing subtest. Students with low vision scored lower on kinesthetic perception and writing performance than sighted peers. The correlation between scores for writing performance and upper extremity kinesthetic sense in the two groups was significant (r = -.34). The probability of deficiencies in kinesthetic information in students with low vision must be remembered.

  6. Le soja local en Allemagne, une demande soutenue, une offre qui s’étoffe

    Directory of Open Access Journals (Sweden)

    Recknagel Jürgen

    2015-09-01

    Full Text Available Depuis 2009, la sole de soja ne cesse d’augmenter en Allemagne, surtout dans le sud du pays mais aussi à l’est et un peu partout dans les régions au climat propice. Un programme national a permis de créer les références nécessaires pour un conseil qualifié apporté aux agriculteurs via un réseau de développement. Ainsi toute une filière soja est déjà bien avancée dans le sud et en cours de mise en place dans le reste du pays, pour organiser la collecte auprès des producteurs et obtenir une offre groupée pour les transformateurs pour l’alimentation animale et humaine. Le soja allemand ne veut pas rivaliser avec le soja OGM ni pour instant avec le soja non-OGM des Amériques mais vise plutôt les filières courtes régionales et le marché bio qui est encore plus déficitaire en auto-approvisionnement que le conventionnel. Avec 10 000 ha en 2014, dont 25 % en bio, le soja en Allemagne est encore loin de la surface du maïs grain (2008–2014 autour de 500 000 ha. En pratique, 20 % de ces surfaces de maïs au climat a priori propice pourraient représenter le potentiel réel pour le soja en Allemagne, sous condition de prix garantissant une rentabilité suffisante par rapport aux autres grandes cultures. Pour les programmes non-OGM des grands distributeurs, il faut de toute façon une base de production élargie comme celle proposée par l’initiative Danube-Soja, qui dans une version Europe-Soja engloberait aussi la France. Avec le verdissement de la PAC et la montée du cours du Dollar par rapport à l’Euro, les perspectives pour une augmentation de la surface de production de soja en Allemagne et en Europe paraissent bonnes. Maintenant il faut travailler sur les débouchés pour garantir l’absorption de la production grandissante par les marchés et les consommateurs à tous les niveaux : régional, national et européen.

  7. Le microdosage des engrais, une innovation qui profite aux femmes

    International Development Research Centre (IDRC) Digital Library (Canada)

    non seulement une diminution de leurs revenus, mais doivent aussi composer avec une pénurie chronique de céréales. Au Niger, par exemple, 2,5 millions de personnes ont eu besoin d'une aide alimentaire en 2005, par suite d'une grave sécheresse (PAM, 2010). Cette situation s'est reproduite en 2010, la mauvaise.

  8. Vision Assessment and Prescription of Low Vision Devices

    OpenAIRE

    Keeffe, Jill

    2004-01-01

    Assessment of vision and prescription of low vision devices are part of a comprehensive low vision service. Other components of the service include training the person affected by low vision in use of vision and other senses, mobility, activities of daily living, and support for education, employment or leisure activities. Specialist vision rehabilitation agencies have services to provide access to information (libraries) and activity centres for groups of people with impaired vision.

  9. The role of vision processing in prosthetic vision.

    Science.gov (United States)

    Barnes, Nick; He, Xuming; McCarthy, Chris; Horne, Lachlan; Kim, Junae; Scott, Adele; Lieby, Paulette

    2012-01-01

    Prosthetic vision provides vision which is reduced in resolution and dynamic range compared to normal human vision. This comes about both due to residual damage to the visual system from the condition that caused vision loss, and due to limitations of current technology. However, even with limitations, prosthetic vision may still be able to support functional performance which is sufficient for tasks which are key to restoring independent living and quality of life. Here vision processing can play a key role, ensuring that information which is critical to the performance of key tasks is available within the capability of the available prosthetic vision. In this paper, we frame vision processing for prosthetic vision, highlight some key areas which present problems in terms of quality of life, and present examples where vision processing can help achieve better outcomes.

  10. Autostéréogramme d'une montagne gaussienne -utilisant une structure paradoxale périodique comme texture de camouflage-

    OpenAIRE

    Colonna , Jean-François

    2011-01-01

    Autostereogram -using a periodical paradoxal structure as a desguise texture- with an hidden gaussian mountain (Autostéréogramme d'une montagne gaussienne -utilisant une structure paradoxale périodique comme texture de camouflage-)

  11. A Dynamic Systems Theory Model of Visual Perception Development

    Science.gov (United States)

    Coté, Carol A.

    2015-01-01

    This article presents a model for understanding the development of visual perception from a dynamic systems theory perspective. It contrasts to a hierarchical or reductionist model that is often found in the occupational therapy literature. In this proposed model vision and ocular motor abilities are not foundational to perception, they are seen…

  12. Auto adaptation incluant une double mobilité logicielle et physique ...

    African Journals Online (AJOL)

    Dans ce papier, nous étudions les possibilités d'auto adaptation que pourrait offrir un calcul réparti incluant une double mobilité : d'une part une mobilité physique des sites supports d'exécution et, d'autre part, une mobilité des composants logiciels métiers ou clients. Cette mobilité de niveau logiciel est envisagée dans le ...

  13. Does functional vision behave differently in low-vision patients with diabetic retinopathy?--A case-matched study.

    Science.gov (United States)

    Ahmadian, Lohrasb; Massof, Robert

    2008-09-01

    A retrospective case-matched study designed to compare patients with diabetic retinopathy (DR) and other ocular diseases, managed in a low-vision clinic, in four different types of functional vision. Reading, mobility, visual motor, and visual information processing were measured in the patients (n = 114) and compared with those in patients with other ocular diseases (n = 114) matched in sex, visual acuity (VA), general health status, and age, using the Activity Inventory as a Rasch-scaled measurement tool. Binocular distance visual acuity was categorized as normal (20/12.5-20/25), near normal (20/32-20/63), moderate (20/80-20/160), severe (20/200-20/400), profound (20/500-20/1000), and total blindness (20/1250 to no light perception). Both Wilcoxon matched pairs signed rank test and the sign test of matched pairs were used to compare estimated functional vision measures between DR cases and controls. Cases ranged in age from 19 to 90 years (mean age, 67.5), and 59% were women. The mean visual acuity (logMar scale) was 0.7. Based on the Wilcoxon signed rank test analyses and after adjusting the probability for multiple comparisons, there was no statistically significant difference (P > 0.05) between patients with DR and control subjects in any of four functional visions. Furthermore, diabetic retinopathy patients did not differ (P > 0.05) from their matched counterparts in goal-level vision-related functional ability and total visual ability. Visual impairment in patients with DR appears to be a generic and non-disease-specific outcome that can be explained mainly by the end impact of the disease in the patients' daily lives and not by the unique disease process that results in the visual impairment.

  14. Le mélanome malin: une tumeur rare des fosses nasales - à propos d'une série de 10 cas

    Science.gov (United States)

    Errachdi, Amal; Epala, Brice Nkoua; Asabbane, Amal; Kabbali, Naoual; Hemmich, Mariem; Kebdani, Tayeb; Benjaafar, Noureddine

    2014-01-01

    Le mélanome malin des fosses nasales est une tumeur rare mais très agressive, de traitement complexe et de pronostic défavorable. Son traitement relève en principe d'une prise en charge essentiellement chirurgicale complétée par une radiothérapie. L'objectif de ce travail est de rapporter les caractéristiques cliniques, thérapeutiques et évolutives des mélanomes des fosses nasales. Nous avons analysé rétrospectivement 10 cas de mélanomes des fosses nasales suivis à l'institut national d'oncologie de Rabat. La rhinoscopie avec biopsie a permis la confirmation histologique du diagnostic de mélanome. Le bilan d'extension comprenait une tomodensitométrie ou imagerie par résonnance magnétique du massif facial, une radiographie thoracique et une échographie abdominale. Dans notre série, l’âge médian était de 67.5 ans, avec une prédominance féminine (7femmes et 3hommes). Le délai médian de découverte était de 6 mois. Deux patients étaient métastatiques d'emblée, et toutes les tumeurs étaient localement avancées au moment du diagnostic. Sept patients ont été opérés avec des limites chirurgicales envahies dans 2 cas et 3 patients étaient inopérables. 2 patients ont été irradiés après la chirurgie et 2 patients ont reçu une chimiothérapie arrêtée au moment de la progression. Deux patients ont récidivé après traitement, et un patient était en mauvais état général et a bénéficié uniquement de soins palliatifs. Tous les patients sont décédés avec un délai médian de survie de 12 mois. Le mélanome malin muqueux des fosses nasales, bien que rare, demeure une pathologie de pronostic défavorable et pose des problèmes de prise en charge. PMID:25404963

  15. Voyage en Paulie-Laurencie, essai sur une construction narrative polyphonique

    Directory of Open Access Journals (Sweden)

    2002-01-01

    Full Text Available Approche analytique de la représentation latino-américaine textuelle et graphique d’un voyageur bordelais du XIXe siècle, dans la revue Le Tour du Monde. Un récit qui fusionne temps et espaces à travers le prisme du regard d’un Occidental satirique, rebelle et misanthrope. Cette traversée interocéanique aux confins de l’histoire, de l’ethnographie, des sciences en général et d’une stratégie du montage hybride mi-fictionnel mi-réel, génère une poétique exotique et singulière. Une poétique qui puise à la mémoire aussi bien un infini renouveau qu’une amertume infinie. L’écriture d’une errance recomposée devient alors cathartique dans la mise en scène de l’ego souffrant de Paul Marcoy poursuivant inlassablement la quête d’une reconnaissance scientifique qu’on lui dénie certes, mais plus encore l’impossible rencontre avec un moi se dérobant sans cesse. VIAJE EN PAULIE-LAURENCIE, ENSAYO SOBRE UNA CONSTRUCCIÓN NARRATIVA POLIFÓNICA. Estudio analítico de la representación latino-americana textual y gráfica de un viajero del siglo XIX oriundo de Burdeos, en la revista Le Tour du Monde. Un relato en que fusionan tiempos y espacios a través del prisma de la mirada satírica, rebelde y misantrópica de un occidental. Aquella travesía interoceánica que entrelaza historia, etnografía, ciencias en general mediante una estrategia del montaje híbrido entre ficción y realidad, genera una exótica y singular poética. Dicha poética, saca de la memoria tanto un renuevo como una amargura insondables e infinitos. La escritura de un vagabundeo recompuesto llega a ser catártica en la escenificación del ego doliente de Paul Marcoy que persigue incansablemente no sólo un reconocimiento científico, que se le niega sin lugar a dudas, sino también el imposible encuentro con un “yo” que sin cesar se le escapa. An analytical approach to the graphic and textual Latin-American perception of a nineteenth century traveller

  16. Application of the SP theory of intelligence to the understanding of natural vision and the development of computer vision.

    Science.gov (United States)

    Wolff, J Gerard

    2014-01-01

    The SP theory of intelligence aims to simplify and integrate concepts in computing and cognition, with information compression as a unifying theme. This article is about how the SP theory may, with advantage, be applied to the understanding of natural vision and the development of computer vision. Potential benefits include an overall simplification of concepts in a universal framework for knowledge and seamless integration of vision with other sensory modalities and other aspects of intelligence. Low level perceptual features such as edges or corners may be identified by the extraction of redundancy in uniform areas in the manner of the run-length encoding technique for information compression. The concept of multiple alignment in the SP theory may be applied to the recognition of objects, and to scene analysis, with a hierarchy of parts and sub-parts, at multiple levels of abstraction, and with family-resemblance or polythetic categories. The theory has potential for the unsupervised learning of visual objects and classes of objects, and suggests how coherent concepts may be derived from fragments. As in natural vision, both recognition and learning in the SP system are robust in the face of errors of omission, commission and substitution. The theory suggests how, via vision, we may piece together a knowledge of the three-dimensional structure of objects and of our environment, it provides an account of how we may see things that are not objectively present in an image, how we may recognise something despite variations in the size of its retinal image, and how raster graphics and vector graphics may be unified. And it has things to say about the phenomena of lightness constancy and colour constancy, the role of context in recognition, ambiguities in visual perception, and the integration of vision with other senses and other aspects of intelligence.

  17. Stereo-vision and 3D reconstruction for nuclear mobile robots

    International Nuclear Information System (INIS)

    Lecoeur-Taibi, I.; Vacherand, F.; Rivallin, P.

    1991-01-01

    In order to perceive the geometric structure of the surrounding environment of a mobile robot, a 3D reconstruction system has been developed. Its main purpose is to provide geometric information to an operator who has to telepilot the vehicle in a nuclear power plant. The perception system is split into two parts: the vision part and the map building part. Vision is enhanced with a fusion process that rejects bas samples over space and time. The vision is based on trinocular stereo-vision which provides a range image of the image contours. It performs line contour correlation on horizontal image pairs and vertical image pairs. The results are then spatially fused in order to have one distance image, with a quality independent of the orientation of the contour. The 3D reconstruction is based on grid-based sensor fusion. As the robot moves and perceives its environment, distance data is accumulated onto a regular square grid, taking into account the uncertainty of the sensor through a sensor measurement statistical model. This approach allows both spatial and temporal fusion. Uncertainty due to sensor position and robot position is also integrated into the absolute local map. This system is modular and generic and can integrate 2D laser range finder and active vision. (author)

  18. Inactivité physique et nombre d'heures passées devant la télévision chez les adultes autochtones asthmatiques : analyse transversale de l'Enquête auprès des peuples autochtones

    Directory of Open Access Journals (Sweden)

    N. Doggett

    2015-01-01

    Full Text Available Contexte : Notre analyse visait à déterminer l'association entre l'asthme et le niveau d'activité physique ainsi qu'avec le nombre d'heures d'activités sédentaires chez les adultes autochtones et visait à comprendre l'influence de l'inactivité physique et du nombre d'heures d'activités sédentaires sur l'utilisation des soins de santé par les adultes autochtones asthmatiques. Méthodologie : Notre analyse a porté sur 20 953 répondants adultes de l'Enquête auprès des peuples autochtones de 2006. Nous avons considéré que les répondants étaient atteints d'asthme « actuel » s'ils avaient déclaré avoir reçu un diagnostic d'asthme de la part d'un médecin et s'ils avaient une ordonnance valide pour des médicaments contre l'asthme. Notre définition d'une activité physique insuffisante correspondait au fait de pratiquer moins de 3 heures d'activité physique modérée à intense par semaine, et notre définition d'un nombre élevé d'heures passées devant la télévision correspondait au fait de regarder la télévision pendant plus de 10 heures par semaine. Nous avons évalué l'utilisation des soins de santé à l'aide du nombre de consultations de professionnels de la santé et du nombre d'hospitalisations d'au moins une nuit. Résultats : Les adultes autochtones asthmatiques étaient plus susceptibles de déclarer un nombre élevé d'heures passées devant la télévision (RC = 1,16; IC : 1,11 à 1,22 et une activité physique insuffisante (RC = 1,15; IC : 1,10 à 1,20 que les non-asthmatiques. Les asthmatiques ayant déclaré un nombre élevé d'heures passées devant la télévision ont signalé plus de consultations de professionnels de la santé au cours des 12 derniers mois (RC = 2,59; IC : 2,34 à 2,87, plus d'hospitalisations d'au moins une nuit au cours de la dernière année (RC = 1,95; IC : 1,82 à 2,08 et plus d'hospitalisations d'au moins une nuit au cours des 5 dernières années (RC = 1,13; IC : 1,07 à 1

  19. Low Vision

    Science.gov (United States)

    ... USAJobs Home » Statistics and Data » Low Vision Listen Low Vision Low Vision Defined: Low Vision is defined as the best- ... Ethnicity 2010 U.S. Age-Specific Prevalence Rates for Low Vision by Age, and Race/Ethnicity Table for 2010 ...

  20. Une tumeur exceptionnelle du doigt: la tumeur fibreuse solitaire

    Directory of Open Access Journals (Sweden)

    Taoufiq Harmouch

    2011-12-01

    Full Text Available La tumeur Fibreuse solitaire (TFS est une proliferation fusocellulaire rare, souvent de localisation intrathoracique. Nous rapportons le cas d�une localisation exceptionnelle au niveau du 3eme doigt de la main droite. En l�absence de marqueur specifique l�interpretation de l�immunomarquage depend du contexte histomorphologique. La similitude avec les differents neoplasmes a cellules fusiformes des tissus mous rend le diagnostic de ces tumeurs mesenchymateuses difficile et tardif. Dans 20a 30 % des cas le comportement de la TFS est celui d�une tumeur maligne localement agressive et recidivante, avec des metastases rares et tardives. Ce comportement impose une surveillance prolongee apres exerese chirurgicale.

  1. “Psycho redux”. Une architecture au second degré

    OpenAIRE

    Hasoo, Alan

    2014-01-01

    Psycho, film réalisé en 1960 par Alfred Hitchcock, est aujourd'hui un classique du cinéma. Une des preuves de ce succès est le grand nombre de reprises, suites et précédents produits. Ensemble, ces interprétations, copies, usages de la forme initiale, composent une “trajectoire”, dans laquelle une œuvre n'est originale qu'à travers ses reproductions. Dans cette “trajectoire”, le remake scène à scène, plan à plan de Gus Van Sant occupe une place particulière. Le film original y est transposé d...

  2. Attentional effects on preattentive vision: Spatial precues affect the detection of simple features

    NARCIS (Netherlands)

    Theeuwes, J.; Kramer, A.F.; Atchley, P.

    1999-01-01

    Most accounts of visual perception hold that the detection of primitive features occurs preattentively, in parallel across the visual field. Evidence that preattentive vision operates without attentional limitations comes from visual search tasks in which the detection of the presence or absence of

  3. Global motion perception is associated with motor function in 2-year-old children.

    Science.gov (United States)

    Thompson, Benjamin; McKinlay, Christopher J D; Chakraborty, Arijit; Anstice, Nicola S; Jacobs, Robert J; Paudel, Nabin; Yu, Tzu-Ying; Ansell, Judith M; Wouldes, Trecia A; Harding, Jane E

    2017-09-29

    The dorsal visual processing stream that includes V1, motion sensitive area V5 and the posterior parietal lobe, supports visually guided motor function. Two recent studies have reported associations between global motion perception, a behavioural measure of processing in V5, and motor function in pre-school and school aged children. This indicates a relationship between visual and motor development and also supports the use of global motion perception to assess overall dorsal stream function in studies of human neurodevelopment. We investigated whether associations between vision and motor function were present at 2 years of age, a substantially earlier stage of development. The Bayley III test of Infant and Toddler Development and measures of vision including visual acuity (Cardiff Acuity Cards), stereopsis (Lang stereotest) and global motion perception were attempted in 404 2-year-old children (±4 weeks). Global motion perception (quantified as a motion coherence threshold) was assessed by observing optokinetic nystagmus in response to random dot kinematograms of varying coherence. Linear regression revealed that global motion perception was modestly, but statistically significantly associated with Bayley III composite motor (r 2 =0.06, Pmotor scores (r 2 =0.06, pmotor and fine motor scores, but unaided visual acuity was not statistically significantly associated with any of the motor scores. These results demonstrate that global motion perception and binocular vision are associated with motor function at an early stage of development. Global motion perception can be used as a partial measure of dorsal stream function from early childhood. Copyright © 2017 Elsevier B.V. All rights reserved.

  4. Hallucination chez Flaubert : poétique de la perception

    Directory of Open Access Journals (Sweden)

    Tomoko Hashimoto

    2009-01-01

    Full Text Available Notre étude vise à montrer dans le cadre d’une poétique du discours réaliste la manière dont l’« hallucination » fonctionne, se construit et trouve sa signification chez Flaubert. Par quels procédés fait-il surgir des mots le caractère éphémère des images et l’intensité de leur perception ?Notre étude se développera en une forme de triptyque, où le contexte, l’avant-texte et le texte seront examinés. Mais, ces trois points constituant ensemble l’œuvre de Flaubert, nous ne les séparerons pas à...

  5. À la recherche des effets d’une plate-forme d’enseignement/ apprentissage en ligne sur les pratiques pédagogiques d’une université : premières approches

    Directory of Open Access Journals (Sweden)

    Marcel Lebrun

    2008-01-01

    Full Text Available L’Université catholique de Louvain (Belgique a mis en place une plate-forme d’enseignement/apprentissage en ligne en 2001. Nous basant sur l’hypothèse de l’effet catalyseur des technologies sur le changement pédagogique, nous avons interrogé les étudiants et les enseignants sur leur perception de ces changements. Les cours qui font appel à iCampus mettent-ils en œuvre des pratiques pédagogiques plus actives que les cours «traditionnels»? Les résultats de cette enquête sont encourageants. Par ailleurs, cette enquête ouvre des pistes concernant la manière d’observer les effets de ce genre de plate-forme sur les pratiques pédagogiques.

  6. De l’approche communicative à une approche cognitive

    Directory of Open Access Journals (Sweden)

    YING Xiaohua

    2016-11-01

    Full Text Available Avec l’apparition de l’approche communicative, la centration de l’enseignement/apprentissage des langues se déplace de l’objet-langue aux pratiques de l’objet-langue, ce qui marque un tournant épistémologique dans l’histoire de l’enseignement/apprentissage des langues. En tant que successeur de l’approche communicative, la perspective actionnelle souligne, de plus, une activité pédagogique guidée par la tâche, ce qui la dote d’une dimension cognitive plus saillante. Une approche cognitive qui se focalise sur la résolution de problèmes et qui tient compte au plus près du processus d’apprentissage de l’apprenant a vu ainsi le jour récemment et indique une nouvelle perspective aux méthodologies de l’enseignement des langues.

  7. A Hybrid Vision-Map Method for Urban Road Detection

    Directory of Open Access Journals (Sweden)

    Carlos Fernández

    2017-01-01

    Full Text Available A hybrid vision-map system is presented to solve the road detection problem in urban scenarios. The standardized use of machine learning techniques in classification problems has been merged with digital navigation map information to increase system robustness. The objective of this paper is to create a new environment perception method to detect the road in urban environments, fusing stereo vision with digital maps by detecting road appearance and road limits such as lane markings or curbs. Deep learning approaches make the system hard-coupled to the training set. Even though our approach is based on machine learning techniques, the features are calculated from different sources (GPS, map, curbs, etc., making our system less dependent on the training set.

  8. Computer use and health hazard: perceptions from Nigeria's ...

    African Journals Online (AJOL)

    Computer use and health hazard: perceptions from Nigeria's Premier University. ... the combination of headache, vision and ergonomic related problems. ... and pains and Repetitive Strain Injury (RSI) and Carpal Tunnel Syndrome (CTS) as ...

  9. De Masaccio à Stalker: pour une esthétique du seuil et de son franchissement 

    Directory of Open Access Journals (Sweden)

    Sylvie Castets

    2010-04-01

    Full Text Available Le seuil,abordé en tant que sujet représenté, est ici le moyen d’envisager la question  de la limite et de son dépassement dans le territoire de l’œuvre peinte, de l’installation et de la performance. La fresque de Masaccio, intitulée « Adam et Ève chassés du Paradis », réalisée vers 1425, constitue une étape décisive dans le traitement de l’espace de représentation. La suggestion d’une  profondeur, mais également, d’une épaisseur, apparaît, faisant basculer la peinture vers le naturalisme. Ainsi, au réalisme intellectuel du Moyen Age, se substitue un nouveau mode de figuration. L’artiste de la Renaissance quitte donc un territoire artistique pour explorer et poser les bases d’un art inédit. Dès lors, la toile, telle une zone de friction, se place et agit dans l’interstice séparant l’espace réel et l’espace représenté. La vision du spectateur, face au tableau, franchit ainsi le barrage de l’œuvre pour coloniser une fable topique amenée par l’illusion de la profondeur. La peinture est également le lieu où l’artiste révèle au spectateur, par le biais de stratagèmes plastiques, ses conditions de réalisation. A partir de là, une rupture s’opère entre la représentation et le fait de présenter. Art et vie s’interpénètrent alors, dans des installations ou des performances, offrant au spectateur un lieu milieu, dans lequel il est amené à s’affranchir de ces modèles. L’oeuvre est donc un seuil qu’il faut «traverser pour apprendre la solitude. » (Serres. Elle vibre d’instabilité et cristallise l’état singulier du changement. Enfin, elle conduit inéluctablement vers un devenir autre.The threshold as theme of representation is in this article used as a way to question the limit and its crossing in the territory of the painted work, of the installation and the performance. Masaccio’s fresco “The Expulsion from the Garden of Eden” of 1425 constitutes a decisive

  10. Classification en référence à une matrice stochastique

    OpenAIRE

    Verdun , Stéphane; Cariou , Véronique; Qannari , El Mostafa

    2009-01-01

    International audience; Etant donné un tableau de données X portant sur un ensemble de n objets, et une matrice stochastique S qui peut être assimilée à une matrice de transition d'une chaîne de Markov, nous proposons une méthode de partitionnement consistant à appliquer la matrice S sur X de manière itérative jusqu'à convergence. Les classes formant la partition sont déterminées à partir des états stationnaires de la matrice stochastique. Cette matrice stochastique peut être issue d'une matr...

  11. Business plan pour une application Smartphone : du concept au lancement

    OpenAIRE

    Vriamont, Gilles

    2015-01-01

    Création d'une application mobile pour Smartphone. Description théorique concernant la rédaction d'un business plan dans une première partie suivi d'une description théorique des caractéristiques des applications mobiles. Dans une seconde partie, analyse de l'industrie des Smartphones et des applications mobiles suivi de la partie pratique et du développement du produit, partant de la description du produit jusqu'à l'analyse des coûts. Master [120] en Ingénieur de gestion, Université catho...

  12. Psychological factors of the image of the state in the students’ perception

    Directory of Open Access Journals (Sweden)

    Ruslana Karkovska

    2014-09-01

    Full Text Available The article is dedicated to the study of the psychological determination of the state’s image in the students’ perception. The results of empirical research of the influence of the students’ adaptation and orientation to their vision of the state are described in the article. The state image in the perception of student youth was analyzed according to the parameters of the state’s accomplishment assessment, the feeling of a sense of belonging to the state, the sense of vision of the state existence and the assessment of the state power as competent, effective, credible, and strong.

  13. Pose Self-Calibration of Stereo Vision Systems for Autonomous Vehicle Applications.

    Science.gov (United States)

    Musleh, Basam; Martín, David; Armingol, José María; de la Escalera, Arturo

    2016-09-14

    Nowadays, intelligent systems applied to vehicles have grown very rapidly; their goal is not only the improvement of safety, but also making autonomous driving possible. Many of these intelligent systems are based on making use of computer vision in order to know the environment and act accordingly. It is of great importance to be able to estimate the pose of the vision system because the measurement matching between the perception system (pixels) and the vehicle environment (meters) depends on the relative position between the perception system and the environment. A new method of camera pose estimation for stereo systems is presented in this paper, whose main contribution regarding the state of the art on the subject is the estimation of the pitch angle without being affected by the roll angle. The validation of the self-calibration method is accomplished by comparing it with relevant methods of camera pose estimation, where a synthetic sequence is used in order to measure the continuous error with a ground truth. This validation is enriched by the experimental results of the method in real traffic environments.

  14. Pose Self-Calibration of Stereo Vision Systems for Autonomous Vehicle Applications

    Science.gov (United States)

    Musleh, Basam; Martín, David; Armingol, José María; de la Escalera, Arturo

    2016-01-01

    Nowadays, intelligent systems applied to vehicles have grown very rapidly; their goal is not only the improvement of safety, but also making autonomous driving possible. Many of these intelligent systems are based on making use of computer vision in order to know the environment and act accordingly. It is of great importance to be able to estimate the pose of the vision system because the measurement matching between the perception system (pixels) and the vehicle environment (meters) depends on the relative position between the perception system and the environment. A new method of camera pose estimation for stereo systems is presented in this paper, whose main contribution regarding the state of the art on the subject is the estimation of the pitch angle without being affected by the roll angle. The validation of the self-calibration method is accomplished by comparing it with relevant methods of camera pose estimation, where a synthetic sequence is used in order to measure the continuous error with a ground truth. This validation is enriched by the experimental results of the method in real traffic environments. PMID:27649178

  15. Envenimation mortelle par morsure de serpent chez une femme ...

    African Journals Online (AJOL)

    Les auteurs rapportent un cas de morsure de serpent au niveau de la face chez une femme enceinte, dont l'évolution a été marquée par l'installation d'un oedème cervico-facial nécessitant une trachéotomie en urgence, et une mort foetale in utero avec troubles de l'hémostase responsable du décès maternel dans un ...

  16. Predictive factors for final outcome of severely traumatized eyes with no light perception

    Directory of Open Access Journals (Sweden)

    Agrawal Rupesh

    2012-06-01

    Full Text Available Abstract Background An eye injury that causes no light perception (NLP typically carries an unfavorable prognosis, and NLP because of trauma is a common indication for enucleation. With advances in vitreoretinal surgical techniques, however, the indication for enucleation is no longer determined by posttrauma NLP vision alone. There are limited studies in the literature to analyse the outcome of NLP eyes following open globe injury. The current study was aimed to evaluate the outcome of surgical repair of severely traumatized eyes with no light perception vision as preoperative visual acuity. Secondary objective was to possibly predict the factors affecting the final vision outcome in this eyes. Methods Retrospective case analysis of patients with surgical repair of open globe injury over last ten years at a tertiary referral eye care centre in Singapore. Results Out of one hundred and seventy two eyes with open globe injury 27 (15.7% eyes had no light perception (NLP. After surgical repair, final visual acuity remained NLP in 18 (66.7% eyes. Final vision improved to Light perception/ Hand movement (LP/HM in 2(7.4% eyes, 1/200 to 19/200(11.1% in 3 eyes and 20/50-20/200(14.8% in 4 eyes. The median follow up was 18.9 months (range: 4–60 months. The factors contributing to poor postoperative outcome were presence of RAPD (p = 0.014, wound extending into zone III (p = 0.023 and associated vitreoretinal trauma (p = 0.008. Conclusions One third of eyes had ambulatory vision or better though two third of eyes still remained NLP. Pre-operative visual acuity of NLP should not be an indication for primary enucleation or evisceration for severely traumatized eyes. Presence of afferent papillary defect, wound extending posterior to rectus insertion and associated vitreoretinal trauma can adversely affect the outcome in severely traumatized eyes with NLP. Timely intervention and state of art surgery may restore useful vision in severely

  17. Perspectives de la rupture quantique 2025-2050 : vers une interprétation quantique du Knowledge Marketing et une NBIC(Q)S Convergence

    OpenAIRE

    CURBATOV, Oleg

    2015-01-01

    International audience; Perspectives de la rupture quantique 2025-2050 : vers une interprétation quantique du Knowledge Marketing et une NBIC(Q)S Convergence ----------------par Oleg Curbatov, chapitre d'ouvrage : « Knowledge Marketing : être compétent dans une économie compétitive », Impressum, 2015 ---------------------------- Les recherches qui ont été porté à la fois sur la connaissance du consommateur, la compétence du client et les situations de co-création, nous ont permis d " explorer...

  18. Bio-indicateurs de la fertilité des sols et la perception paysanne à l ...

    African Journals Online (AJOL)

    SARAH

    30 mai 2015 ... d'identifier des bio-indicateurs des sols fertiles et des sols dégradés selon la perception paysanne et des paramètres ..... effet, une augmentation du stock hydrique du sol à ... Fonctionnement et gestion des écosystèmes.

  19. Genèse d’une communauté virtuelle d’apprenants dans le cadre d’une démarche d’apprentissage collaboratif à distance

    Directory of Open Access Journals (Sweden)

    Sylvie Grosjean

    2008-03-01

    Full Text Available L’objectif de cet article est de présenter une analyse du processus d’émergence d’une communauté virtuelle d’apprenants dans le cadre d’une démarche d’apprentissage collaboratif à distance. Par conséquent, nous proposons une analyse empirique de la phase initiale de développement d’une communauté virtuelle d’apprenants, que nous nommons la phase d’engagement, afin de mieux la décrire et la comprendre. Pour ce faire, nous procédons à une analyse des interactions communicatives entre étudiants en s'appuyant sur l’étude de formes langagières et instrumentées de communication s'accomplissant lors d’échanges asynchrones (via un forum de discussion. The aim of this article is to analyse the emergence of the learner’s virtual community by analysing the interactions between subjects communicating via a discussion forum. We propose an empirical analysis of the initial phase of development that we name the engagement phase in the collaborative online learning setting . We will present an empirical analysis of an interactive dynamic through the analysis of linguistic (electronic conversation and non linguistic (artefacts, intermediary objects forms of communication.

  20. Sharpening vision by adapting to flicker

    Science.gov (United States)

    Arnold, Derek H.; Williams, Jeremy D.; Phipps, Natasha E.; Goodale, Melvyn A.

    2016-01-01

    Human vision is surprisingly malleable. A static stimulus can seem to move after prolonged exposure to movement (the motion aftereffect), and exposure to tilted lines can make vertical lines seem oppositely tilted (the tilt aftereffect). The paradigm used to induce such distortions (adaptation) can provide powerful insights into the computations underlying human visual experience. Previously spatial form and stimulus dynamics were thought to be encoded independently, but here we show that adaptation to stimulus dynamics can sharpen form perception. We find that fast flicker adaptation (FFAd) shifts the tuning of face perception to higher spatial frequencies, enhances the acuity of spatial vision—allowing people to localize inputs with greater precision and to read finer scaled text, and it selectively reduces sensitivity to coarse-scale form signals. These findings are consistent with two interrelated influences: FFAd reduces the responsiveness of magnocellular neurons (which are important for encoding dynamics, but can have poor spatial resolution), and magnocellular responses contribute coarse spatial scale information when the visual system synthesizes form signals. Consequently, when magnocellular responses are mitigated via FFAd, human form perception is transiently sharpened because “blur” signals are mitigated. PMID:27791115

  1. Modeling the convergence accommodation of stereo vision for binocular endoscopy.

    Science.gov (United States)

    Gao, Yuanqian; Li, Jinhua; Li, Jianmin; Wang, Shuxin

    2018-02-01

    The stereo laparoscope is an important tool for achieving depth perception in robot-assisted minimally invasive surgery (MIS). A dynamic convergence accommodation algorithm is proposed to improve the viewing experience and achieve accurate depth perception. Based on the principle of the human vision system, a positional kinematic model of the binocular view system is established. The imaging plane pair is rectified to ensure that the two rectified virtual optical axes intersect at the fixation target to provide immersive depth perception. Stereo disparity was simulated with the roll and pitch movements of the binocular system. The chessboard test and the endoscopic peg transfer task were performed, and the results demonstrated the improved disparity distribution and robustness of the proposed convergence accommodation method with respect to the position of the fixation target. This method offers a new solution for effective depth perception with the stereo laparoscopes used in robot-assisted MIS. Copyright © 2017 John Wiley & Sons, Ltd.

  2. Fusillades scolaires : construction d’une catégorie et savoirs explicatifs d’une forme de violence juvénile

    OpenAIRE

    Paton, Nathalie

    2016-01-01

    Dans cet article, l’auteure présente une revue de la littérature, sous deux angles complémentaires, concernant la notion de school shooting, c’est-à-dire les fusillades commises au sein des établissements scolaires par des élèves. Elle examine d’abord la manière dont la notion a été forgée aux États-Unis au sein des débats publics en relation à une autre forme de violence juvénile, celle des gangs des milieux populaires des grandes villes, avant de constituer une forme de violence autonome, s...

  3. Computational gestalts and perception thresholds.

    Science.gov (United States)

    Desolneux, Agnès; Moisan, Lionel; Morel, Jean-Michel

    2003-01-01

    In 1923, Max Wertheimer proposed a research programme and method in visual perception. He conjectured the existence of a small set of geometric grouping laws governing the perceptual synthesis of phenomenal objects, or "gestalt" from the atomic retina input. In this paper, we review this set of geometric grouping laws, using the works of Metzger, Kanizsa and their schools. In continuation, we explain why the Gestalt theory research programme can be translated into a Computer Vision programme. This translation is not straightforward, since Gestalt theory never addressed two fundamental matters: image sampling and image information measurements. Using these advances, we shall show that gestalt grouping laws can be translated into quantitative laws allowing the automatic computation of gestalts in digital images. From the psychophysical viewpoint, a main issue is raised: the computer vision gestalt detection methods deliver predictable perception thresholds. Thus, we are set in a position where we can build artificial images and check whether some kind of agreement can be found between the computationally predicted thresholds and the psychophysical ones. We describe and discuss two preliminary sets of experiments, where we compared the gestalt detection performance of several subjects with the predictable detection curve. In our opinion, the results of this experimental comparison support the idea of a much more systematic interaction between computational predictions in Computer Vision and psychophysical experiments.

  4. Color vision in ADHD: part 2--does attention influence color perception?

    Science.gov (United States)

    Kim, Soyeon; Al-Haj, Mohamed; Fuller, Stuart; Chen, Samantha; Jain, Umesh; Carrasco, Marisa; Tannock, Rosemary

    2014-10-24

    To investigate the impact of exogenous covert attention on chromatic (blue and red) and achromatic visual perception in adults with and without Attention Deficit Hyperactivity Disorder (ADHD). Exogenous covert attention, which is a transient, automatic, stimulus-driven form of attention, is a key mechanism for selecting relevant information in visual arrays. 30 adults diagnosed with ADHD and 30 healthy adults, matched on age and gender, performed a psychophysical task designed to measure the effects of exogenous covert attention on perceived color saturation (blue, red) and contrast sensitivity. The effects of exogenous covert attention on perceived blue and red saturation levels and contrast sensitivity were similar in both groups, with no differences between males and females. Specifically, exogenous covert attention enhanced the perception of blue saturation and contrast sensitivity, but it had no effect on the perception of red saturation. The findings suggest that exogenous covert attention is intact in adults with ADHD and does not account for the observed impairments in the perception of chromatic (blue and red) saturation.

  5. Slow angled-descent forepaw grasping (SLAG): an innate behavioral task for identification of individual experimental mice possessing functional vision.

    Science.gov (United States)

    Gil-Pagés, Macarena; Stiles, Robert J; Parks, Christopher A; Neier, Steven C; Radulovic, Maja; Oliveros, Alfredo; Ferrer, Alejandro; Reed, Brendan K; Wilton, Katelynn M; Schrum, Adam G

    2013-08-23

    There is significant interest in the generation of improved assays to clearly identify experimental mice possessing functional vision, a property that could qualify mice for inclusion in behavioral and neuroscience studies. Widely employed current methods rely on mouse responses to visual cues in assays of reflexes, depth perception, or cognitive memory. However, commonly assessed mouse reflexes can sometimes be ambiguous in their expression, while depth perception assays are sometimes confounded by variation in anxiety responses and exploratory conduct. Furthermore, in situations where experimental groups vary in their cognitive memory capacity, memory assays may not be ideal for assessing differences in vision. We have optimized a non-invasive behavioral assay that relies on an untrained, innate response to identify individual experimental mice possessing functional vision: slow angled-descent forepaw grasping (SLAG). First, we verified that SLAG performance depends on vision and not olfaction. Next, all members of an age-ranged cohort of 158 C57BL/6 mice (57 wild-type, 101 knockout, age range 44-241 days) were assessed for functional vision using the SLAG test without training or conditioning. Subjecting the population to a second innate behavioral test, Dark Chamber preference, corroborated that the functional vision assessment of SLAG was valid. We propose that the SLAG assay is immediately useful to quickly and clearly identify experimental mice possessing functional vision. SLAG is based on a behavioral readout with a significant innate component with no requirement for training. This will facilitate the selection of mice of known sighted status in vision-dependent experiments that focus on other types of behavior, neuroscience, and/or cognitive memory.

  6. Tumeur d'Abrikossoff juxta axillaire: une localisation rare d'une tumeur très rare, à propos d'un cas

    Science.gov (United States)

    Amourak, Sarah; Bouzoubaa, Wael; Jayi, Sofia; Alaoui, Fatimazahra Fdili; Chaara, Hikmat; Melhouf, Moulay Abdelilah

    2015-01-01

    Décrite pour la première fois en 1926 par Abrikossoff, les tumeurs à cellules granuleuses (TCG) sont bénignes et uniques dans la grande majorité des cas. Les principales localisations sont la cavité orale, puis les tissus sous-cutanés de la tête et du cou et les seins. La pathogenèse a été longtemps débattue, après avoir proposé initialement une origine musculaire striée les études récentes sont en faveur d'une origine neurogène schwannienne confirmées par une étude immunohistochimique. Le traitement de la tumeur à cellules granuleuses est un traitement chirurgical, il permet un diagnostic de certitude par l'examen anatomo-pathologique de la pièce d'exérèse qui doit rechercher les limites d'exérèse et la présence de critères de malignité. Leur évolution est souvent favorable si la résection chirurgicale est complète. Nous rapportons ici le cas d'une tumeur d'Abrikossoff à localisation juxta axillaire et nous profitons de faire une revue de la littérature afin de mettre le point sur cette entité rare. PMID:26328001

  7. Two eyes, one vision: binocular motion perception in human visual cortex

    NARCIS (Netherlands)

    Barendregt, M.

    2016-01-01

    An important aspect of human vision is the fact that it is binocular, i.e. that we have two eyes. As a result, the brain nearly always receives two slightly different images of the same visual scene. Yet, we only perceive a single image and thus our brain has to actively combine the binocular visual

  8. Une offre publique de documents ?

    OpenAIRE

    Tesnière, Valérie

    2017-01-01

    TOUT NUMÉRIQUE ? LE LIVRE CONCURRENCÉ ? LA BIBLIOTHÈQUE CONCURRENCÉE ? La fracture numérique reste une réalité comme l’attestent encore des chiffres cités par Le Monde : une évolution de la couverture Internet dans le monde à l’horizon 2009-2030 donnerait la projection suivante : 24,7 % des 6,8 milliards d’habitants de la planète sont connectés en 2009 et l’on atteindrait 50 % pour 8,2 milliards d’habitants en 2030. Cela interroge indirectement le statut futur du papier : sera-t-il l’apanage ...

  9. The organization of shape and color in vision and art.

    Science.gov (United States)

    Pinna, Baingio

    2011-01-01

    The aim of this work is to study the phenomenal organization of shape and color in vision and art in terms of microgenesis of the object perception and creation. The idea of "microgenesis" is that the object perception and creation takes time to develop. Our hypothesis is that the roles of shape and color are extracted in sequential order and in the same order these roles are also used by artists to paint objects. Boundary contours are coded before color contours. The microgenesis of the object formation was demonstrated (i) by introducing new conditions derived from the watercolor illusion, where the juxtaposed contours are displaced horizontally or vertically, and based on variations of Matisse's Woman, (ii) by studying descriptions and replications of visual objects in adults and children of different ages, and (iii) by analyzing the linguistic sequence and organization in a free naming task of the attributes related to shape and color. The results supported the idea of the microgenesis of the object perception, namely the temporal order in the formation of the roles of the object properties (shape before color). Some general principles were extracted from the experimental results. They can be a starting point to explore a new domain focused on the microgenesis of shape and color within the more general problem of object organization, where integrated and multidisciplinary studies based on art and vision science can be very useful.

  10. The organization of shape and color in Vision and Art

    Directory of Open Access Journals (Sweden)

    Baingio ePinna

    2011-10-01

    Full Text Available The aim of this work is to study the phenomenal organization of shape and color in vision and art in terms of microgenesis of the object perception and creation. The idea of ‘microgenesis’ is that the object perception and creation takes time to develop. Our hypothesis is that the roles of shape and color are extracted in sequential order and in the same order these roles are also used by artists to paint objects. Boundary contours are coded before color contours. The microgenesis of the object formation was demonstrated (i by introducing new conditions derived from the watercolor illusion, where the juxtaposed contours are displaced horizontally or vertically, and based on variations of Matisse’s Woman, (ii by studying descriptions and replications of visual objects in adults and children of different ages, and (iii by analyzing the linguistic sequence and organization in a free naming task of the attributes related to shape and color. The results supported the idea of the microgenesis of the object perception, namely the temporal order in the formation of the roles of the object properties (shape before color. Some general principles were extracted from the experimental results. They can be a starting point to explore a new domain focused on the microgenesis of shape and color within the more general problem of object organization, where integrated and multidisciplinary studies based on art and vision science can be very useful.

  11. Writing Helpful Feedback: The Influence of Feedback Type on Students' Perceptions and Writing Performance

    Directory of Open Access Journals (Sweden)

    Alyssa Taylor

    2011-12-01

    Full Text Available Written feedback on students’ assignments is a common method that instructors and teaching assistants use to inform students about their performance or guide revisions. Despite its frequency of use, written feedback often lacks sufficient detail to be beneficial to students, and additional empirical research should examine its effectiveness as a teaching tool. The current study examined the effectiveness of two different types of feedback, developed and undeveloped, in terms of its influence on students’ subsequent writing performance and students’ perceptions of the feedback. Results demonstrated that the type of feedback significantly affected students’ perceptions, with developed feedback related to higher ratings of fairness and helpfulness; however, this feedback did not have a significant positive effect on students’ written performance.Les commentaires écrits sur les travaux sont une méthode courante utilisée par les enseignants et les aides-enseignants pour renseigner les étudiants sur leurs performances ou pour orienter les révisions. Malgré leur fréquence, il arrive souvent que les commentaires écrits ne soient pas assez détaillés pour être profitables aux étudiants. De plus amples recherches empiriques devraient se pencher sur l’efficacité de cet outil d'enseignement. La présente étude porte sur l'efficacité de différents types de commentaires élaborés et sous-élaborés; sur leur influence sur la performance écrite subséquente des étudiants et sur la perception de ces derniers à propos des commentaires. Les résultats démontrent que le type de commentaires influe significativement sur la perception des étudiants, les commentaires élaborés entraînant des évaluations supérieures en ce qui a trait à l’impartialité et à l'utilité; cependant, ces commentaires n'ont pas d'effets positifs importants sur la performance écrite des étudiants.

  12. TUMEUR ORBITAIRE: MANIFESTATION INITIALE D'UNE MALADIE ...

    African Journals Online (AJOL)

    L'hétérogénéité et la rareté des formes multicentriques de la maladie de Castleman font que leurs traitements soient très disparates. La maladie de Castleman doit être considérée comme un diagnostic possible d'une adénopathie cervicale particulièrement chez les patients souffrant d'une maladie inflammatoire chronique.

  13. Une terreur par l’image

    Directory of Open Access Journals (Sweden)

    Annie DULONG

    2011-09-01

    Full Text Available Si d’autres événements — Hiroshima, la découverte des camps de concentration, la chute du mur de Berlin — ont, au cours du XXe siècle, marqué suffisamment l’imaginaire pour trouver leur réponse dans des œuvres d’art, le 11 septembre 2001 pose la question de la fictionnalisation autrement : il ne s’agit plus tant de combler les manques de la représentation, liés à l’absence d’images ou au délai dans leur dévoilement, mais bien de composer avec l’omniprésence d’une représentation martelée à la télévision et sur Internet. Que cette représentation soit partielle, tronquée et qu’il lui manque la présence des corps, ces grands absents des photographies et des images tournées par les journalistes, ne change rien au fait que c’est avec le trop-plein que les artistes doivent maintenant négocier.Cet article s’intéresse aux romans qui traitent l’événement de front au lieu de l’aborder sur un mode mineur, et a pour objectif de tracer un portrait de la représentation des médias dans les romans du 11 septembre 2001. Ces romans, outre le fait qu’ils traitent des événements de New York, ont comme point commun un personnage, ou décor : les médias, représentés par la télévision, l’Internet, les photographies de presse, interviennent dans les récits d’une manière significative et témoignent de la force brute des images. À travers une étude de certains des mécanismes à l’œuvre dans The Writing on the Wall (Lynne Sharon Schwartz, Extremely Loud and Incredibly Close (Jonathan Safran Foer, Falling Man (Don DeLillo et A Disorder Peculiar to the Country (Ken Kalfus, il s’agira de proposer des réponses à ces quelques questions : quel rôle les médias jouent-ils, et comment participent-ils au récit ? Quelle pression les images exercent-elles sur les personnages ? Que révèlent les personnages enfants dans leur rapport aux médias ? Quelle critique, finalement, les romans

  14. 3D Vision Provides Shorter Operative Time and More Accurate Intraoperative Surgical Performance in Laparoscopic Hiatal Hernia Repair Compared With 2D Vision.

    Science.gov (United States)

    Leon, Piera; Rivellini, Roberta; Giudici, Fabiola; Sciuto, Antonio; Pirozzi, Felice; Corcione, Francesco

    2017-04-01

    The aim of this study is to evaluate if 3-dimensional high-definition (3D) vision in laparoscopy can prompt advantages over conventional 2D high-definition vision in hiatal hernia (HH) repair. Between September 2012 and September 2015, we randomized 36 patients affected by symptomatic HH to undergo surgery; 17 patients underwent 2D laparoscopic HH repair, whereas 19 patients underwent the same operation in 3D vision. No conversion to open surgery occurred. Overall operative time was significantly reduced in the 3D laparoscopic group compared with the 2D one (69.9 vs 90.1 minutes, P = .006). Operative time to perform laparoscopic crura closure did not differ significantly between the 2 groups. We observed a tendency to a faster crura closure in the 3D group in the subgroup of patients with mesh positioning (7.5 vs 8.9 minutes, P = .09). Nissen fundoplication was faster in the 3D group without mesh positioning ( P = .07). 3D vision in laparoscopic HH repair helps surgeon's visualization and seems to lead to operative time reduction. Advantages can result from the enhanced spatial perception of narrow spaces. Less operative time and more accurate surgery translate to benefit for patients and cost savings, compensating the high costs of the 3D technology. However, more data from larger series are needed to firmly assess the advantages of 3D over 2D vision in laparoscopic HH repair.

  15. What's next? New evidence for prediction in human vision.

    Science.gov (United States)

    Enns, James T; Lleras, Alejandro

    2008-09-01

    Everyday visual experience involves making implicit predictions, as revealed by our surprise when something disturbs our expectations. Many theories of vision have been premised on the central role played by prediction. Yet, implicit prediction in human vision has been difficult to assess in the laboratory, and many results have not distinguished between the indisputably important role of memory and the future-oriented aspect of prediction. Now, a new and unexpected finding - that humans can resume an interrupted visual search much faster than they can start a new search - offers new hope, because the rapid resumption of a search seems to depend on participants forming an implicit prediction of what they will see after the interruption. These findings combined with results of recent neurophysiology studies provide a framework for studying implicit prediction in perception.

  16. Rationality, perception, and the all-seeing eye

    NARCIS (Netherlands)

    Felin, Teppo; Koenderink, Jan|info:eu-repo/dai/nl/070864543; Krueger, Joachim I

    Seeing-perception and vision-is implicitly the fundamental building block of the literature on rationality and cognition. Herbert Simon and Daniel Kahneman's arguments against the omniscience of economic agents-and the concept of bounded rationality-depend critically on a particular view of the

  17. The handicap of abnormal colour vision.

    Science.gov (United States)

    Cole, Barry L

    2004-07-01

    All people with abnormal colour vision, except for a few mildly affected deuteranomals, report that they experience problems with colour in everyday life and at work. Contemporary society presents them with increasing problems because colour is now so widely used in printed materials and in computer displays. Equal opportunity law gives them protection against unfair discrimination in employment, so a decision to exclude a person from employment on the grounds of abnormal colour vision must now be well supported by good evidence and sound argument. This paper reviews the investigations that have contributed to understanding the nature and consequences of the problems they have. All those with abnormal colour vision are at a disadvantage with comparative colour tasks that involve precise matching of colours or discrimination of fine colour differences either because of their loss of colour discrimination or anomalous perception of metamers. The majority have problems when colour is used to code information, in man-made colour codes and in naturally occurring colour codes that signal ripeness of fruit, freshness of meat or illness. They can be denied the benefit of colour to mark out objects and organise complex visual displays. They may be unreliable when a colour name is used as an identifier. They are slower and less successful in search when colour is an attribute of the target object or is used to organise the visual display. Because those with the more severe forms of abnormal colour vision perceive a very limited gamut of colours, they are at a disadvantage in the pursuit and appreciation of those forms of art that use colour.

  18. A Vision and Change Reform of Introductory Biology Shifts Faculty Perceptions and Use of Active Learning

    Science.gov (United States)

    Auerbach, Anna Jo; Schussler, Elisabeth

    2017-01-01

    Increasing faculty use of active-learning (AL) pedagogies in college classrooms is a persistent challenge in biology education. A large research-intensive university implemented changes to its biology majors’ two-course introductory sequence as outlined by the Vision and Change in Undergraduate Biology Education final report. One goal of the curricular reform was to integrate core biological concepts and competencies into the courses using AL pedagogical approaches. The purpose of this study was to observe the instructional practices used by faculty (N = 10) throughout the 3-year process of reform to determine whether the use of AL strategies (including student collaboration) increased, given that it can maximize student learning gains. Instructors participated in yearly interviews to track any change in their perceptions of AL instruction. Instructors increased their average use of AL by 12% (group AL by 8%) of total class time throughout the 3-year study. Interviews revealed that instructors shifted their definitions of AL and talked more about how to assess student learning over the 3 years of the project. Collaboration, feedback, and time may have been important factors in the reform, suggesting that small shifts over time can accumulate into real change in the classroom. PMID:29146663

  19. MIMETISME ET IMITATION : UNE REVUE DE LA LITTERATURE

    African Journals Online (AJOL)

    l‟imitation «des idées pures», mais aussi l‟existence d‟un type de protection de .... gion qui diffuse les caractéristiques de la mode d‟une organisation à une autre. ... d‟amélioration des performances mais par besoin de légitimité. La.

  20. Scanpath-based analysis of objects conspicuity in context of human vision physiology.

    Science.gov (United States)

    Augustyniak, Piotr

    2007-01-01

    This paper discusses principal aspects of objects conspicuity investigated with use of an eye tracker and interpreted on the background of human vision physiology. Proper management of objects conspicuity is fundamental in several leading edge applications in the information society like advertisement, web design, man-machine interfacing and ergonomics. Although some common rules of human perception are applied since centuries in the art, the interest of human perception process is motivated today by the need of gather and maintain the recipient attention by putting selected messages in front of the others. Our research uses the visual tasks methodology and series of progressively modified natural images. The modifying details were attributed by their size, color and position while the scanpath-derived gaze points confirmed or not the act of perception. The statistical analysis yielded the probability of detail perception and correlations with the attributes. This probability conforms to the knowledge about the retina anatomy and perception physiology, although we use noninvasive methods only.

  1. Operational Based Vision Assessment Automated Vision Test Collection User Guide

    Science.gov (United States)

    2017-05-15

    AFRL-SA-WP-SR-2017-0012 Operational Based Vision Assessment Automated Vision Test Collection User Guide Elizabeth Shoda, Alex...June 2015 – May 2017 4. TITLE AND SUBTITLE Operational Based Vision Assessment Automated Vision Test Collection User Guide 5a. CONTRACT NUMBER... automated vision tests , or AVT. Development of the AVT was required to support threshold-level vision testing capability needed to investigate the

  2. Using brain stimulation to disentangle neural correlates of conscious vision.

    Science.gov (United States)

    de Graaf, Tom A; Sack, Alexander T

    2014-01-01

    Research into the neural correlates of consciousness (NCCs) has blossomed, due to the advent of new and increasingly sophisticated brain research tools. Neuroimaging has uncovered a variety of brain processes that relate to conscious perception, obtained in a range of experimental paradigms. But methods such as functional magnetic resonance imaging or electroencephalography do not always afford inference on the functional role these brain processes play in conscious vision. Such empirical NCCs could reflect neural prerequisites, neural consequences, or neural substrates of a conscious experience. Here, we take a closer look at the use of non-invasive brain stimulation (NIBS) techniques in this context. We discuss and review how NIBS methodology can enlighten our understanding of brain mechanisms underlying conscious vision by disentangling the empirical NCCs.

  3. L’ensemble du Main Building au CERN à Genève, Peter Steiger et Rudolf Steiger architectes, Carl Hubacher, Fietz et Hauri ingénieurs, 1954-1960 recommandations pour une réhabilitation

    CERN Document Server

    Wohlschlag, Jérôme; Marino, Giulia

    Les bâtiments qui ont écrit l’histoire de l’architecture moderne vivent une période décisive: souffrant de nombreux maux dus à leurs âges, d’une méconnaissance, et parfois même d’une certaine impopularité, les menaces sont de plus en plus concrètes: d’une transformation normative et inadaptée jusqu’à la démolition. Ces oeuvres représentent un réel patrimoine pour la collectivité, que les effets du temps ont fini par occulter. Le vieillissement et le pragmatisme quotidien transformant l’édifice, les qualités qui l’ont placé au statut qu’on lui a reconnu ne sont presque plus perceptibles. Pourtant, ces édifices recèlent un grand potentiel; pour les maîtres d’ouvrage au bénéfice d’un bien valorisé, exploité et emblématique d’une part; pour la société enrichissant son patrimoine culturel d’autre part; finalement pour les architectes comme moyen de connaissance, source d’inspiration et ressource professionnelle. Le site du CERN à Meyrin, de par son extrater...

  4. Perceptual geometry of space and form: visual perception of natural scenes and their virtual representation

    Science.gov (United States)

    Assadi, Amir H.

    2001-11-01

    Perceptual geometry is an emerging field of interdisciplinary research whose objectives focus on study of geometry from the perspective of visual perception, and in turn, apply such geometric findings to the ecological study of vision. Perceptual geometry attempts to answer fundamental questions in perception of form and representation of space through synthesis of cognitive and biological theories of visual perception with geometric theories of the physical world. Perception of form and space are among fundamental problems in vision science. In recent cognitive and computational models of human perception, natural scenes are used systematically as preferred visual stimuli. Among key problems in perception of form and space, we have examined perception of geometry of natural surfaces and curves, e.g. as in the observer's environment. Besides a systematic mathematical foundation for a remarkably general framework, the advantages of the Gestalt theory of natural surfaces include a concrete computational approach to simulate or recreate images whose geometric invariants and quantities might be perceived and estimated by an observer. The latter is at the very foundation of understanding the nature of perception of space and form, and the (computer graphics) problem of rendering scenes to visually invoke virtual presence.

  5. The ontology of vision. The invisible, consciousness of Living matter.

    Directory of Open Access Journals (Sweden)

    Giorgia eFiorio

    2016-02-01

    Full Text Available If I close my eyes, the absence of light activates the peripheral cells devoted to the perception of darkness. The awareness of ‘seeing oneself seeing’ is in its essence a thought, one that is internal to the vision and previous to any object of sight. To this amphibious faculty, the diaphanous color of darkness, Aristotle assigns the principle of knowledge. Vision is a whole perceptual system, not a channel of sense. Functions of vision are interweaved to the texture of human interaction within a terrestrial environment that is in turn contained into the cosmic order. Within the internal resonance of a double reflection, the living being is the transitive host between two orders of scale, both bigger and smaller than the individual and unity. In the perceptual integrative system of human vision, the convergence-divergence of the corporeal presence and the diffraction of its own appearance is the margin. The sensation of being no longer coincides with the breath of life, it does not seems ‘real’ without the trace of some visible evidence and its simultaneous ‘sharing.’ Without a shadow, without an imprint, and destined for multiple invisible witnesses, the numeric copia of the physical presence inhabits the transient memory of our electronic prostheses. A rudimentary ‘visuality’ replaces tangible experience dissipating its meaning and the awareness of being alive. Transversal to the civilizations of the ancient world, through different orders of function and status, the anthropomorphic figuration of archaic sculpture questions the idea of Being. Ancient statues do not appear in order to be visible as artworks, but rather to exist. The awareness of human finiteness seals the compulsion to ‘give body’ to an invisible apparition that shapes the figuration of Being as the corporeal expression of an ontogenetic waking of human consciousness.Subject and object, the term humanum fathoms the relationship between matter and its living

  6. Color Functionality Used in Visual Display for Occupational and Environmental Safety and Managing Color Vision Deficiency.

    Science.gov (United States)

    Ochiai, Nobuhisa; Kondo, Hiroyuki

    2017-01-01

    The effects of color perception are utilized in visual displays for the purpose of safety in the workplace and in daily life. These effects, generally known as color functionality, are divided into four classifications: visibility, legibility, conspicuity and discriminability. This article focuses on the relationship between the color functionality of color schemes used in visual displays for occupational and environmental safety and color vision deficiency (particularly congenital red-green color deficiency), a critical issue in ophthalmology, and examines the effects of color functionality on the perception of the color red in individuals with protan defects. Due to abrupt system reforms, current Japanese clinical ophthalmology finds itself in a situation where it is insufficiently prepared to handle congenital red-green color deficiencies. Indeed, occupational problems caused by color vision deficiencies have been almost completely neglected, and are an occupational safety and health concern that will need to be solved in the future. This report will present the guidelines for the color vision testing established by the British Health and Safety Executive (HSE), a pioneering example of a model meant to solve these problems. Issues relating to the creation of guidelines adapted to Japanese clinical ophthalmology will also be examined, and we will discuss ways to utilize color functionality used in visual displays for occupational and environmental safety to help manage color vision deficiency.

  7. The impact of pediatric vision disorders in adulthood.

    Science.gov (United States)

    Davidson, Stefanie; Quinn, Graham E

    2011-02-01

    In addition to refractive errors such as myopia and astigmatism, ocular disorders that occur in infants, toddlers, and children may present lifelong problems for the child. Conditions such as strabismus, amblyopia, and retinopathy of prematurity may require adaptations in adulthood. In addition, vision disorders that occur in childhood may manifest as problems well into adulthood. When visual impairment is present, there may be further effects on overall health, self-perception, educational attainment, job choices, and a number of other social factors.

  8. Fiches « En une page » | CRDI - Centre de recherches pour le ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    10 nov. 2010 ... Fiche « En une page » de MCP no 1. Un IED sans envergure, une croissance stagnante : le Mercosur peut-il faire mieux ? Fiche « En une page » de MCP no 2. Impôts, taxes et équité entre les sexes : codes, comportements et conséquences, voulues ou non. Fiche « En une page » de MCP no 3.

  9. Une énergie, des énergies

    CERN Document Server

    Salviat, Béatrice; Allégraud, Katia

    2015-01-01

    Pour se chauffer, se déplacer, communiquer, agir en artiste, l'énergie est indispensable. Omniprésente dans les débats géopolitiques, galvaudée par les slogans publicitaires, l'énergie hante notre société. Elle se conserve, mais s'épuise. Elle se manifeste partout, dans l'eau qui coule, dans les atomes qui se désintègrent ou fusionnent, mais pas toujours sous la forme qui conviendrait au moment voulu. Et pire, la voilà désormais associée aux pollutions ! Cet ouvrage présente dans une première partie les signes perceptibles de l'énergie dans notre vie quotidienne (le feu, la vapeur...), puis ceux qui se produisent en nous et autour de nous, du vivant végétal (qui transforme l'énergie lumineuse en énergie chimique) jusqu'aux confins de l'Univers. La deuxième partie raconte la manière dont les humains détournent à leur profit ces transformations énergétiques diverses pour se nourrir, se déplacer, se loger, fabriquer des objets, alimenter leurs industries, créer ou communiquer. La tr...

  10. Examining age-related shared variance between face cognition, vision, and self-reported physical health: a test of the common cause hypothesis for social cognition

    Science.gov (United States)

    Olderbak, Sally; Hildebrandt, Andrea; Wilhelm, Oliver

    2015-01-01

    The shared decline in cognitive abilities, sensory functions (e.g., vision and hearing), and physical health with increasing age is well documented with some research attributing this shared age-related decline to a single common cause (e.g., aging brain). We evaluate the extent to which the common cause hypothesis predicts associations between vision and physical health with social cognition abilities specifically face perception and face memory. Based on a sample of 443 adults (17–88 years old), we test a series of structural equation models, including Multiple Indicator Multiple Cause (MIMIC) models, and estimate the extent to which vision and self-reported physical health are related to face perception and face memory through a common factor, before and after controlling for their fluid cognitive component and the linear effects of age. Results suggest significant shared variance amongst these constructs, with a common factor explaining some, but not all, of the shared age-related variance. Also, we found that the relations of face perception, but not face memory, with vision and physical health could be completely explained by fluid cognition. Overall, results suggest that a single common cause explains most, but not all age-related shared variance with domain specific aging mechanisms evident. PMID:26321998

  11. Examining Age-Related Shared Variance Between Face Cognition, Vision, and Self-Reported Physical Health: A Test of the Common Cause Hypothesis for Social Cognition

    Directory of Open Access Journals (Sweden)

    Sally eOlderbak

    2015-08-01

    Full Text Available The shared decline in cognitive abilities, sensory functions (e.g., vision and hearing, and physical health with increasing age is well documented with some research attributing this shared age-related decline to a single common cause (e.g., aging brain. We evaluate the extent to which the common cause hypothesis predicts associations between vision and physical health with social cognition abilities, specifically face perception and face memory. Based on a sample of 443 adults (17 to 88 years old, we test a series of structural equation models, including Multiple Indicator Multiple Cause (MIMIC models, and estimate the extent to which vision and self-reported physical health are related to face perception and face memory through a common factor, before and after controlling for their fluid cognitive component and the linear effects of age. Results suggest significant shared variance amongst these constructs, with a common factor explaining some, but not all, of the shared age-related variance. Also, we found that the relations of face perception, but not face memory, with vision and physical health could be completely explained by fluid cognition. Overall, results suggest that a single common cause explains most, but not all age-related shared variance with domain specific aging mechanisms evident.

  12. Vision in Children and Adolescents with Autistic Spectrum Disorder: Evidence for Reduced Convergence

    Science.gov (United States)

    Milne, Elizabeth; Griffiths, Helen; Buckley, David; Scope, Alison

    2009-01-01

    Evidence of atypical perception in individuals with ASD is mainly based on self report, parental questionnaires or psychophysical/cognitive paradigms. There have been relatively few attempts to establish whether binocular vision is enhanced, intact or abnormal in those with ASD. To address this, we screened visual function in 51 individuals with…

  13. Visual Motion Perception

    Science.gov (United States)

    1991-08-15

    displace- ment limit for motion in random dots," Vision Res., 24, 293-300. Pantie , A. & K. Turano (1986) "Direct comparisons of apparent motions...Hicks & AJ, Pantie (1978) "Apparent movement of successively generated subjec. uve figures," Perception, 7, 371-383. Ramachandran. V.S. & S.M. Anstis...thanks think deaf girl until world uncle flag home talk finish short thee our screwdiver sonry flower wrCstlir~g plan week wait accident guilty tree

  14. Temporal dynamics of figure-ground segregation in human vision.

    Science.gov (United States)

    Neri, Peter; Levi, Dennis M

    2007-01-01

    The segregation of figure from ground is arguably one of the most fundamental operations in human vision. Neural signals reflecting this operation appear in cortex as early as 50 ms and as late as 300 ms after presentation of a visual stimulus, but it is not known when these signals are used by the brain to construct the percepts of figure and ground. We used psychophysical reverse correlation to identify the temporal window for figure-ground signals in human perception and found it to lie within the range of 100-160 ms. Figure enhancement within this narrow temporal window was transient rather than sustained as may be expected from measurements in single neurons. These psychophysical results prompt and guide further electrophysiological studies.

  15. La syphilis congenitale revelee par une fracture spontanee

    Directory of Open Access Journals (Sweden)

    Mounia Lakhdar Idrissi

    2011-11-01

    Full Text Available Alors qu�elle est actuellement oubliee dans les pays developpes, la syphilis congenitale se voit encore chez nous faute du depistage antenatal. Ses formes cliniques sont polymorphes et orientent a tord vers d�autres pathologies surtout en periode neonatale. Le diagnostic n�est donc pas toujours facile. La revelation d�une syphilis congenitale par une fracture spontanee est exceptionnellement decrite. Nous rapportons dans ce travail le cas d�un nourrisson de 2 mois ramene en consultation pour limitation douloureuse des mouvements du bras droit. Le diagnostic est evoque sur les donnees radiologiques et confirme par la serologie syphilitique. Le traitement a repose essentiellement sur l�administration de la penicilline G avec une bonne evolution clinique.

  16. Social Perception of Hydrogen Technologies: The View of Spanish Stake holders; Percepcion Social de las Tecnologias del Hidrogeno. La Vision de los Stakeholders Espanoles

    Energy Technology Data Exchange (ETDEWEB)

    Ferri Anglada, S.

    2013-07-01

    This technical report presents an overview of the social perception and vision of a sample of Spanish stake holders on hydrogen technologies. The study is based on the implementation of a survey, combining both quantitative and qualitative data. An ad hoc electronic survey was design to collect views and perceptions on several key factors regarding this innovative energy alternative. The group of experts participating (N=130) in the study, comes mainly from research centers, universities and private companies. The survey addresses three major themes: expert views, social acceptability, and contextual factors of hydrogen technologies. The aim is to capture both the current and the future scene as viewed by the experts on hydrogen technologies, identifying key factors in terms of changes, uncertainties, obstacles and opportunities. The objective is to identify potential key features for the introduction, development, promotion, implementation, and large-scale deployment of a highly successful energy proposal in countries such as Iceland, one of the pioneers in base its economy on hydrogen technologies. To conclude, this report illustrates the positive engagement of a sample of Spanish stake holders towards hydrogen technologies that may prove vital in the transition towards the Hydrogen Economy in Spain. (Author)

  17. Lenteur et vision : l’empreinte du western dans le roman français contemporain

    Directory of Open Access Journals (Sweden)

    Elisa Bricco

    2012-12-01

    Full Text Available Par-delà l’effet rebound, où le cinéma entre dans la littérature par la transposition de ses techniques scripturales et de composition, l’on assiste aujourd’hui à une véritable intégration des stylèmes et des topoï cinématographiques dans le roman. Par une analyse minutieuse de Pas le bon pas le truand de Patrick Chatelier, l’on interroge ici ce processus d’assimilation qui travaille la matière du texte du point de vue thématique et structural. L’écrivain démontre une grande attention aux structures créatives cinématographiques qu’il utilise pour composer son texte. À partir de la réécriture d’une séquence filmique de Sergio Leone, il assimile à sa matière textuelle deux procédés de création : le ralenti et la vision. Le ralenti permet de raconter les scènes dans les moindres détails, mais aussi de mimer le champ/contrechamp ; la primauté de l’aspect visuel dans la construction du récit met en scène une réalité en équilibre entre vrai et vraisemblable filmique.Beyond the rebound effect, where the movie enters into the literature by transposition of scriptural and composition techniques, we are now witnessing a true integration of cinema stylèmes and topoï in the novel. By a deep analysis of Patrick Chatelier’s Pas le bon pas le truand, we question this assimilation process that works the material of the text in terms of thematic and structural. The writer demonstrates attention to creative film structures and he uses it to compose his text. In rewriting a scene from a Sergio Leone film, he assimilates into his textual material two processes: the slowness with which the scenes are told in detail, and repeated so as to mimic the changes in visual perspective, the shot / reverse shot, and the primacy of the visual in the constructionof the narrative, which depicts a true balance between reality and film probability.

  18. Pediatric Low Vision

    Science.gov (United States)

    ... Asked Questions Español Condiciones Chinese Conditions Pediatric Low Vision What is Low Vision? Partial vision loss that cannot be corrected causes ... and play. What are the signs of Low Vision? Some signs of low vision include difficulty recognizing ...

  19. Machine-Vision Systems Selection for Agricultural Vehicles: A Guide

    Directory of Open Access Journals (Sweden)

    Gonzalo Pajares

    2016-11-01

    Full Text Available Machine vision systems are becoming increasingly common onboard agricultural vehicles (autonomous and non-autonomous for different tasks. This paper provides guidelines for selecting machine-vision systems for optimum performance, considering the adverse conditions on these outdoor environments with high variability on the illumination, irregular terrain conditions or different plant growth states, among others. In this regard, three main topics have been conveniently addressed for the best selection: (a spectral bands (visible and infrared; (b imaging sensors and optical systems (including intrinsic parameters and (c geometric visual system arrangement (considering extrinsic parameters and stereovision systems. A general overview, with detailed description and technical support, is provided for each topic with illustrative examples focused on specific applications in agriculture, although they could be applied in different contexts other than agricultural. A case study is provided as a result of research in the RHEA (Robot Fleets for Highly Effective Agriculture and Forestry Management project for effective weed control in maize fields (wide-rows crops, funded by the European Union, where the machine vision system onboard the autonomous vehicles was the most important part of the full perception system, where machine vision was the most relevant. Details and results about crop row detection, weed patches identification, autonomous vehicle guidance and obstacle detection are provided together with a review of methods and approaches on these topics.

  20. Compte-rendu de L’éthique clinique : pour une approche relationnelle dans les soins, 2014, Hubert Doucet, Paramètres, Les Presses de l’Université de Montréal

    Directory of Open Access Journals (Sweden)

    Roigt, Delphine

    2017-04-01

    Full Text Available In his book L’éthique clinique pour une approche relationnelle (Clinical Ethics: A Relational Approach, Hubert Doucet proposes an approach to clinical ethics that includes various theoretical and practical perspectives, notably that of the philosopher Paul Ricoeur. Doucet argues for a relational vision of clinical ethics practice, an ethics of caregivers that, in his words, “needs to be built from the experience of the disease and adapted to the ill person.”

  1. Pose Self-Calibration of Stereo Vision Systems for Autonomous Vehicle Applications

    Directory of Open Access Journals (Sweden)

    Basam Musleh

    2016-09-01

    Full Text Available Nowadays, intelligent systems applied to vehicles have grown very rapidly; their goal is not only the improvement of safety, but also making autonomous driving possible. Many of these intelligent systems are based on making use of computer vision in order to know the environment and act accordingly. It is of great importance to be able to estimate the pose of the vision system because the measurement matching between the perception system (pixels and the vehicle environment (meters depends on the relative position between the perception system and the environment. A new method of camera pose estimation for stereo systems is presented in this paper, whose main contribution regarding the state of the art on the subject is the estimation of the pitch angle without being affected by the roll angle. The validation of the self-calibration method is accomplished by comparing it with relevant methods of camera pose estimation, where a synthetic sequence is used in order to measure the continuous error with a ground truth. This validation is enriched by the experimental results of the method in real traffic environments.

  2. Low Vision FAQs

    Science.gov (United States)

    ... de los Ojos Cómo hablarle a su oculista Low Vision FAQs What is low vision? Low vision is a visual impairment, not correctable ... person’s ability to perform everyday activities. What causes low vision? Low vision can result from a variety of ...

  3. From spectral information to animal colour vision: experiments and concepts.

    Science.gov (United States)

    Kelber, Almut; Osorio, Daniel

    2010-06-07

    Many animals use the spectral distribution of light to guide behaviour, but whether they have colour vision has been debated for over a century. Our strong subjective experience of colour and the fact that human vision is the paradigm for colour science inevitably raises the question of how we compare with other species. This article outlines four grades of 'colour vision' that can be related to the behavioural uses of spectral information, and perhaps to the underlying mechanisms. In the first, even without an (image-forming) eye, simple organisms can compare photoreceptor signals to locate a desired light environment. At the next grade, chromatic mechanisms along with spatial vision guide innate preferences for objects such as food or mates; this is sometimes described as wavelength-specific behaviour. Here, we compare the capabilities of di- and trichromatic vision, and ask why some animals have more than three spectral types of receptors. Behaviours guided by innate preferences are then distinguished from a grade that allows learning, in part because the ability to learn an arbitrary colour is evidence for a neural representation of colour. The fourth grade concerns colour appearance rather than colour difference: for instance, the distinction between hue and saturation, and colour categorization. These higher-level phenomena are essential to human colour perception but poorly known in animals, and we suggest how they can be studied. Finally, we observe that awareness of colour and colour qualia cannot be easily tested in animals.

  4. Promotion d'une gouvernance foncière inclusive pour une ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    ... de développer des outils et des stratégies qui facilitent l'accès et le contrôle des femmes sur le foncier; et de formuler des recommandations stratégiques et pratiques permettant une mise en œuvre effective des politiques et des stratégies de gouvernance foncière inclusive qui reconnaissent la place et le rôle de la femme ...

  5. Modélisation et commande d'une chaine de pompage photovoltaique

    OpenAIRE

    MEFLAH, AISSA

    2011-01-01

    L’objectif de ce mémoire est d’assurer une commande vectorielle associée à une électropompe asynchrone immergée. La configuration de ce système comporte un générateur photovoltaïque, un bus PV, un filtre PV connecté à un hacheur survolteur, un bus DC et un onduleur de tension alimentant une machine asynchrone couplée à une pompe centrifuge. L’objectif de ce système consiste à assurer un fonctionnement à puissance maximale du système photovoltaïque pour diverses conditions climatiques. L’ad...

  6. Case Report - Le syndrome de Cri du Chat : A propos d'une ...

    African Journals Online (AJOL)

    Le syndrome du Cri du Chat (Cri du Chat syndrome, CdCS) est une anomalie chromosomique résultant d'une délétion de taille variable de l'extrémité du bras court du chromosome 5 (5p), incluant une région critique située en p15.2. Il représente une des délétions chromosomiques les plus fréquentes, son incidence dans ...

  7. Using Brain Stimulation to Disentangle Neural Correlates of Conscious Vision

    Directory of Open Access Journals (Sweden)

    Tom Alexander de Graaf

    2014-09-01

    Full Text Available Research into the neural correlates of consciousness (NCCs has blossomed, due to the advent of new and increasingly sophisticated brain research tools. Neuroimaging has uncovered a variety of brain processes that relate to conscious perception, obtained in a range of experimental paradigms. But methods such as fMRI or EEG do not always afford inference on the role these brain processes play in conscious vision. Such empirical neural correlates of consciousness could reflect neural prerequisites, neural consequences, or neural substrates of a conscious experience. Here, we take a closer look at the use of non-invasive brain stimulation (NIBS techniques in this context. We discuss and review how NIBS methodology can enlighten our understanding of brain mechanisms underlying conscious vision by disentangling the empirical neural correlates of consciousness.

  8. A machine vision system for the calibration of digital thermometers

    International Nuclear Information System (INIS)

    Vázquez-Fernández, Esteban; Dacal-Nieto, Angel; González-Jorge, Higinio; Alvarez-Valado, Victor; Martín, Fernando; Formella, Arno

    2009-01-01

    Automation is a key point in many industrial tasks such as calibration and metrology. In this context, machine vision has shown to be a useful tool for automation support, especially when there is no other option available. A system for the calibration of portable measurement devices has been developed. The system uses machine vision to obtain the numerical values shown by displays. A new approach based on human perception of digits, which works in parallel with other more classical classifiers, has been created. The results show the benefits of the system in terms of its usability and robustness, obtaining a success rate higher than 99% in display recognition. The system saves time and effort, and offers the possibility of scheduling calibration tasks without excessive attention by the laboratory technicians

  9. Vision Sensor-Based Road Detection for Field Robot Navigation

    Directory of Open Access Journals (Sweden)

    Keyu Lu

    2015-11-01

    Full Text Available Road detection is an essential component of field robot navigation systems. Vision sensors play an important role in road detection for their great potential in environmental perception. In this paper, we propose a hierarchical vision sensor-based method for robust road detection in challenging road scenes. More specifically, for a given road image captured by an on-board vision sensor, we introduce a multiple population genetic algorithm (MPGA-based approach for efficient road vanishing point detection. Superpixel-level seeds are then selected in an unsupervised way using a clustering strategy. Then, according to the GrowCut framework, the seeds proliferate and iteratively try to occupy their neighbors. After convergence, the initial road segment is obtained. Finally, in order to achieve a globally-consistent road segment, the initial road segment is refined using the conditional random field (CRF framework, which integrates high-level information into road detection. We perform several experiments to evaluate the common performance, scale sensitivity and noise sensitivity of the proposed method. The experimental results demonstrate that the proposed method exhibits high robustness compared to the state of the art.

  10. Vers une cartographie géo-lexicale

    Directory of Open Access Journals (Sweden)

    William Martinez

    2011-06-01

    Full Text Available L’analyse statistique de la distribution du vocabulaire dans des guides de tourisme du XIXe et XXe siècle permet d’identifier la terminologie descriptive essentielle telle qu’elle est employée dans ces textes. Une interprétation plus structurée de ces données est possible grâce aux méthodes de cooccurrence qui produisent des cartes de mots associés décrivant l’usage préféré de noms, adjectifs, adverbes, etc. à propos d’une ville, une région ou un itinéraire. À partir de cette visualisation originale de structures de mots, nous envisagerons la convergence des données lexicales et cartographiques dans une base de données de type SIG (Système d’Information Géographique.The statistical analysis of vocabulary distribution in French tourist guides of the 19th and 20th century reveals the essential descriptive terminology used in these texts. A more structured interpretation of this data is made possible by way of co-occurrence methods that produce associated word maps describing the preferred usage of nouns, adjectives, adverbs etc. regarding a given town, region or route. Based on this original visualizing of word structures we will consider the convergence of lexical and cartographic data in a GIS-type database (Geographic Information System.

  11. La division sociale de la langue: la fiction d’une langue populaire

    Directory of Open Access Journals (Sweden)

    Dominique Ducard

    2016-12-01

    Full Text Available L’objectif de cet article est de montrer, à travers un parcours de textes d’historiens et de (sociolinguistes, comment le discours sur la langue française, dans sa formation et son fonctionnement, est traversé par l’idée d’une division sociale constitutive d’une “langue populaire”, identifiée à une classe sociale et dévaluée. Cette investigation interroge la notion de langue et son image dans la conscience linguistique des sujets et conduit à poser la question de l’institution sociale de la langue. La langue commune, pluralisée et diversifiée dans le discours historique et linguistique, se double d’une référence à une langue normée, instituée par l’école, dont les effets ont été soulignés dans les travaux originaux de Renée Balibar. Nous finissons ainsi par une évocation des thèses de cet auteur, avec une mise en perspective de la langue normée, dans son rapport aux styles littéraires, avec la transposition des variations sociales dans la langue de la fiction.

  12. Violence et dire, pour une rhétorique du soin

    Directory of Open Access Journals (Sweden)

    André Quaderi

    Full Text Available Par une approche plurielle (psychopathologie du travail, sciences du langage et psychanalyse et au travers d’une clinique de type groupe de parole en institution gériatrique, il est abordé les phénomènes de violences. Les effets du dire, au niveau du clinicien, induisent des changements de comportements des soignants dont les causes sont abordées. Ainsi, la taylorisation de l’organisation inhibe la relation du soignant à l’autre et fige le travail dans une exécution de tâche. Ces effets délétères sont à rapporter au Thanatos tout comme les effets du dire (interprété comme une rhétorique du soin sont à comprendre du côté de l’Eros.

  13. Le syndrome de Tunnel tarsien : à propos d'une observation au ...

    African Journals Online (AJOL)

    Les auteurs présentent un fait clinique d'une douleur subaiguë de la face médiale du pied gauche, explorée par l'imagerie par résonance magnétique, en complément d'une échographie Doppler. Ces explorations ont permis de faire le diagnostic du syndrome de tunnel tarsien par aponévrosite plantaire secondaire à une ...

  14. ORIENTATION RELATIONNELLE VERSUS TRANSACTIONNELLE DU CLIENT : DEVELOPPEMENT D'UNE ECHELLE DANS LE SECTEUR BANCAIRE FRANÇAIS. UNE ETUDE EXPLORATOIRE

    OpenAIRE

    Benamour , Yasmine; Prim-Allaz , Isabelle

    2000-01-01

    International audience; The authors conduct an exploratory study in order to develop a measurement scale of customers transactional/relational orientation. The study is implemented in the context of French banking industry in both B.-to-C. and B.-to-B. environments. The results show that a different scale is needed for each context.; Les auteurs mettent en place une étude exploratoire dans le but de développer une échelle de mesure de l'orientation transactionnelle/relationnelle du client. Ce...

  15. Perception and eye movements in simulated traffic situations.

    Science.gov (United States)

    Luoma, J

    1984-01-01

    In an experiment to simulate the perception task of a driver, subjects were shown uninterrupted series of colour slides of different kinds of highway scenes. The dependent variables were eye fixations, fixation times and conscious perceptions for the part of the traffic signs and roadside advertisements. Perceptions were achieved mostly as a result of fixation, but partly also by using peripheral vision. On the other hand fixation did not always cause perception. The lengthening of fixation time increased the number of correct perceptions. When the traffic sign and the roadside advertisement were in the same slide, the advertisement disturbed the perception of the sign, but in the daylight conditions this effect was not noticed as an alteration of the fixation of the sign, but as prevention of further information processing. The disturbing influence of the advertisement was increased by its bad information ergonomics which caused a long fixation time.

  16. D’une convergence remarquable entre phénoménologie et philosophie analytique: la lecture ricœurienne des thèses de Sartre et Ryle sur l’imagination

    Directory of Open Access Journals (Sweden)

    Jean-Luc Amalric

    2014-07-01

    Full Text Available The aim of this article is to analyse the meaning and the implications of the comparative interpretation of Sartre’s and Ryle’s theses on imagination that Ricœur undertook in the still unpublished text of his Lectures on Imagination. These lectures were delivered at the University of Chicago in 1975. First, the article shows how Ricœur brings out a strong convergence, both in the method and in the presuppositions, of the Sartrean and Rylean conceptions of imagination : the choice of a descriptive method leads the two philosophers to a common critique of the mental image. Secondly, the article analyses the properly critical side of the Ricœurian interpretation by showing how it eventually brings to light the common theoretical limitation of Sartre’s and Ryle’s theses on imagination. According to Ricœur, those theses lead to a conception of image as picture and fail to consider the image as fiction, and so they remain locked in a theory of reproductive imagination and of the primacy of perception.RésuméCet article se propose d’analyser le sens et les enjeux de la lecture croisée des thèses de Sartre et Ryle sur l’imagination à laquelle se livre Ricœur dans le texte encore inédit des Lectures on imagination professées en 1975 à l’Université de Chicago. Dans un premier temps, il montre comment Ricœur met en relief une convergence forte, de méthode et de présupposés entre les conceptions sartrienne et rylienne de l’imagination : le choix d’une méthode  descriptive conduisant les deux philosophes à une commune critique de l’image mentale. Puis, dans un second temps, il analyse le versant proprement critique de la lecture ricœurienne en montrant comment elle en vient à dénoncer une commune limitation théorique des thèses de Sartre et Ryle sur l’imagination. Selon Ricœur, ces thèses débouchent sur une conception de l’image comme tableau qui échoue à penser l’image comme fiction et elles restent

  17. Grounding Our Vision: Brain Research and Strategic Vision

    Science.gov (United States)

    Walker, Mike

    2011-01-01

    While recognizing the value of "vision," it could be argued that vision alone--at least in schools--is not enough to rally the financial and emotional support required to translate an idea into reality. A compelling vision needs to reflect substantive, research-based knowledge if it is to spark the kind of strategic thinking and insight…

  18. Visual Prosthesis: Interfacing Stimulating Electrodes with Retinal Neurons to Restore Vision

    Directory of Open Access Journals (Sweden)

    Alejandro Barriga-Rivera

    2017-11-01

    Full Text Available The bypassing of degenerated photoreceptors using retinal neurostimulators is helping the blind to recover functional vision. Researchers are investigating new ways to improve visual percepts elicited by these means as the vision produced by these early devices remain rudimentary. However, several factors are hampering the progression of bionic technologies: the charge injection limits of metallic electrodes, the mechanical mismatch between excitable tissue and the stimulating elements, neural and electric crosstalk, the physical size of the implanted devices, and the inability to selectively activate different types of retinal neurons. Electrochemical and mechanical limitations are being addressed by the application of electromaterials such as conducting polymers, carbon nanotubes and nanocrystalline diamonds, among other biomaterials, to electrical neuromodulation. In addition, the use of synthetic hydrogels and cell-laden biomaterials is promising better interfaces, as it opens a door to establishing synaptic connections between the electrode material and the excitable cells. Finally, new electrostimulation approaches relying on the use of high-frequency stimulation and field overlapping techniques are being developed to better replicate the neural code of the retina. All these elements combined will bring bionic vision beyond its present state and into the realm of a viable, mainstream therapy for vision loss.

  19. Prediction of Instability for Miscible Displacements in a Hele-Shaw Cell Prévision de l'instabilité pour des déplacements miscibles dans une cellule Hele-Shaw

    Directory of Open Access Journals (Sweden)

    Coskuner G.

    2006-11-01

    Full Text Available A universal dimensionless scaling group and its critical value at the onset of instability for a miscible displacement in a Hele-Shaw cell is derived. The derivation is based on a variational technique and it is capable of considering, for the first time, the effect of the length of a Hele-Shaw cell on the criterion for the onset of instability. The theory is verified by comparing it with forty-four Hele-Shaw cell experiments. On calcule un groupe universel sans dimension de mise à l'échelle et sa valeur critique au départ de l'instabilité dans un déplacement miscible dans une cellule Hele-Shaw. Ce calcul est basé sur une technique variationnelle et permet, pour la première fois, de prendre en compte l'effet de la longueur d'une cellule Hele-Shaw sur le critère d'apparition d'instabilité. La théorie est vérifiée en la comparant avec des expériences réalisées avec quarante-quatre cellules Hele-Shaw.

  20. Etude de la structure d'une population de truite commune (Salmo trutta L. dans une zone à barbeau

    Directory of Open Access Journals (Sweden)

    BAGLINIERE J. L.

    1981-10-01

    Full Text Available Au total 16 espèces de poissons, dont la truite commune (Salmo trutta L. ont été recensées par pêche électrique dans le cours aval de la rivière Colmont, classée rivière à salmonidés dominants, et un de ses affluents. La présence de gros cyprins d'eaux vives (barbeau, Barbus barbus L., et chevaine, Leuciscus cephalus L. et de quelques espèces de cyprins d'eaux lentes est une caractéristique de la zone à barbeau. Parmi les cyprins, les espèces les plus abondantes sont le goujon (Gobio gobio L. et le chevaine présent dans tous les types d'habitats de la rivière. La population de truites se caractérise par : — une faible densité dans la rivière et l'affluent et par une bonne croissance. Ces deux paramètres montrent des variations annuelles. — une ségrégation spatiale des classes d'âge ; les truites 0+ sont localisées principalement dans l'affluent, alors que dans la rivière les truites sont âgées d'au moins 1 an et sont présentes uniquement dans les zones rapide-radier. Les caractéristiques de cette population de truite sont discutées en considérant l'interaction possible avec les autres populations pisciaires dans un milieu dont l'habitat est dégradé.

  1. Les facteurs d’influence de l’indépendance de l’auditeur externe: une étude exploratoire auprès des préparateurs de l’information financière tunisiens

    Directory of Open Access Journals (Sweden)

    Omri Mohamed Ali Brahim

    2014-09-01

    Full Text Available Cette étude vise à déterminer les facteurs d’influence de l’indépendance perçue de l’auditeur externe. Afin d’atteindre notre objectif nous avons menée une analyse fondée sur une première phase qualitative et une deuxième quantitative. Cette dernière repose sur un questionnaire adressé à 87 préparateurs d’information financière tunisiens. Notre étude a révélé que les préparateurs de l’information financière construisent leurs perception en privilégiant essentiellement la réputation de l’auditeur externe, suivi par la taille du cabinet, le contrôle de la profession et la responsabilité juridique, les liens personnels, les incompatibilités, les honoraires, la dépendance financière et la rotation des auditeurs.

  2. Une étape primordiale dans l’évaluation d’une politique de développement durable

    Directory of Open Access Journals (Sweden)

    Karine Bourgeois

    2003-11-01

    Full Text Available L’évaluation des politiques publiques prend une place institutionnelle de plus en plus importante. La commande de l’évaluation donne lieu à l’élaboration d’un cahier des charges, qui précise notamment les questions évaluatives stratégiques à traiter. Pour parvenir à une définition judicieuse de ces questions, la réalisation, en amont, d’une démarche interdisciplinaire comprenant une phase d’analyse de politique complétée d’une étude des modalités de mise en oeuvre s’avère nécessaire. A travers l’exemple de l’évaluation intermédiaire du Contrat Territorial d’Exploitation (CTE en Limousin, nous tentons de montrer en quoi le graphe d’objectifs peut constituer un outil adapté pour révéler la théorie d’action de la politique publique. La conception du cahier des charges contribue également à éclairer la décision publique en favorisant l’implication et la concertation des divers partenaires. Celle-ci est d’autant plus précieuse qu’il s’agit d’une politique de développement durable, visant, entre autres, à mieux gérer les biens publics environnementaux.An important step in a sustainable policy evaluation: the conception of terms of reference, The experience of the Land Management Contract mid-term review in Limousin. Terms of reference and particularly evaluative questions definition is one of the most important stage in evaluation process. This last aims to analyse the context of the policy and its theory  of action. In order to define, in a pertinent way, priority evaluative questions, both political analysis and implementation analysis (an interdisciplinary method are required, moreover when the policy is defined in a regional and co-operation framework. In the case of the Land Management Contract (LMC mid-term review, an objective tree has been drawn up to identify which social and economical mechanisms have been implemented to achieve the main objectives of the Limousin program

  3. Le kyste hydatique du cordon spermatique: une localisation exceptionnelle

    Science.gov (United States)

    Hamdane, Mohamed Moncef; Bougrine, Fethi; Msakni, Issam; Dhaoui-Ghozzi, Amen; Bouziani, Ammar

    2011-01-01

    L’ hydatidose est une anthropo-zoonose due au développement chez l'homme de la forme larvaire du taenia Echinococcus granulosis. La plupart des kystes hydatiques se localisent dans le foie et les poumons. Le kyste hydatique du cordon spermatique est extrêmement rare avec seulement 4 cas rapportés dans la littérature. Les auteurs rapportent dans cet article un nouveau cas d'hydatidose du cordon spermatique. Il s'agissait d'un homme de 40 ans qui consultait pour des douleurs scrotales évoluant depuis huit mois. L'examen clinique a mis en évidence une tuméfaction mobile, inguino-scrotale, droite. L’échographie testiculaire a objectivé une hernie inguinale droite associée à deux kystes épididymaires bilatéraux. Le patient a été opéré pour cure de son hernie avec découverte en per-opératoire d'un kyste du cordon spermatique qui a été réséqué. L'examen anatomopathologique a conclu à une hydatidose du cordon spermatique. PMID:22384304

  4. Computational vision

    CERN Document Server

    Wechsler, Harry

    1990-01-01

    The book is suitable for advanced courses in computer vision and image processing. In addition to providing an overall view of computational vision, it contains extensive material on topics that are not usually covered in computer vision texts (including parallel distributed processing and neural networks) and considers many real applications.

  5. Making a vision document tangible using "vision-tactics-metrics" tables.

    Science.gov (United States)

    Drury, Ivo; Slomski, Carol

    2006-01-01

    We describe a method of making a vision document tangible by attaching specific tactics and metrics to the key elements of the vision. We report on the development and early use of a "vision-tactics-metrics" table in a department of surgery. Use of the table centered the vision in the daily life of the department and its faculty, and facilitated cultural change.

  6. 1. Le Soleil, une étoile dans notre Galaxie

    OpenAIRE

    Vial, Jean-Claude

    2017-01-01

    Par une belle nuit sans Lune (et sans nuages), levons les yeux vers le ciel. L’œil est immédiatement attiré par le cortège d’étoiles brillantes qui a donné son nom à la Voie lactée. Il s’agit en fait d’une galaxie de près de 200 milliards d’étoiles qui abrite notre Soleil et ses planètes, c’est notre galaxie, « la » Galaxie, comme une île dans le vaste cosmos. La Galaxie : ses 150 à 200 milliards d’étoiles sont réparties selon des bras spiraux autour d’un noyau central et pour la plupart conf...

  7. Commande adaptive d'une machine asynchrone

    Science.gov (United States)

    Slama-Belkhodja, I.; de Fornel, B.

    1996-06-01

    The paper deals with an indirect self-tuning speed control for an induction motor supplied by a chopper-filter-inverter system. Input/Output models are identified with the recursive least squares algorithm and the controller adaptation is based on a pole assignement strategy. Emphasis is put on the evaluation of the parameter identification in order to avoid instabilities because of disturbances or insufficient excitations. This is especially of importance when the adaptive control is carried out in closed loop systems and without additional test signals. Simulation results show the improvement of the dynamic responses and the robustness against load variations or parameters variations (rotor resistance, inertia). Cat article décrit une stratégie de commande adaptive indirecte à Placement de Pôles (PP), appliquée à la commande en vitesse d'une machine asynchrone alimentée par un ensemble hacheur-filtre-onduleur de tension. L'algorithme des Moindres Carrés Récursifs (MCR) est utilisé pour l'identification des modèles de comportement type entrées/sorties. Un intérêt particulier est porté à la mise en oeuvre de cet algorithme et à la discussion de ses résultats, tenant compte des erreurs de modélisation et de la nature peu riche en excitations des entrées du processus. Différents régimes transitoires ont été simulés pour apprécier l'apport de cette association (MCR-PP) : démarrages et inversion des sens de rotation, à vide et en charges, applications d'échelons de couple résistant, variations paramétriques. Les résultats permettent d'illustrer, tant au niveau des performances que de la robustesse, l'apport d'une telle commande adaptive pour des entraînements électriques avec une machine asynchrone.

  8. Colombie: une guerre privée de sens?

    Directory of Open Access Journals (Sweden)

    2000-01-01

    Full Text Available Voilà plus de vingt ans que la Colombie connaît des phénomènes de violence collective singulièrement aigus et complexes. Depuis le début de la décennie 80, l’intensification de la confrontation entre forces armées, guérillas et paramilitaires a été telle que cette dernière domine désormais le panorama général de la violence. L’intensification du conflit, surtout à l’encontre des populations civiles, a suscité un nombre croissant d’analyses, de commentaires et de réactions diverses. La plupart de ces interprétations privilégient une approche en termes d’irrationalité et de violences éruptives privées de sens. Le propos de cet article est précisément de discuter et confronter cette vision avec une lecture plus rationnelle des faits afin de voir dans quelle mesure la confrontation armée parvient à se structurer dans une trame explicative beaucoup plus intelligible. COLOMBIA: ¿UNA GUERRA SIN SENTIDO?. Desde hace más de veinte años, Colombia conoce fenómenos de violencia colectiva particularmente agudos y complejos. A partir de la década de los 80, la intensificación de la confrontación entre fuerzas armadas, guerrillas y paramilitares ha sido tan significativa que ésta domina ahora el panorama general de la violencia. La intensificación del conflicto, sobre todo contra las poblaciones civiles, ha suscitado un número creciente de análisis, comentarios y reacciones diversas. La mayoría de estas interpretaciones han privilegiado una lectura en términos de irracionalidad y de violencias eruptivas como si el conflicto estuviese privado de cualquier significado. El propósito del artículo es precisamente discutir y confrontar esta visión con un enfoque más racionalista para ver en qué medida la confrontación armada logra estructurarse en una trama explicativa mucho más inteligible. COLOMBIA: A SENSELESS WAR?. For more than two decades now, Colombia has faced the acute and complex phenomena of collective

  9. Perception and psychological evaluation for visual and auditory environment based on the correlation mechanisms

    Science.gov (United States)

    Fujii, Kenji

    2002-06-01

    In this dissertation, the correlation mechanism in modeling the process in the visual perception is introduced. It has been well described that the correlation mechanism is effective for describing subjective attributes in auditory perception. The main result is that it is possible to apply the correlation mechanism to the process in temporal vision and spatial vision, as well as in audition. (1) The psychophysical experiment was performed on subjective flicker rates for complex waveforms. A remarkable result is that the phenomenon of missing fundamental is found in temporal vision as analogous to the auditory pitch perception. This implies the existence of correlation mechanism in visual system. (2) For spatial vision, the autocorrelation analysis provides useful measures for describing three primary perceptual properties of visual texture: contrast, coarseness, and regularity. Another experiment showed that the degree of regularity is a salient cue for texture preference judgment. (3) In addition, the autocorrelation function (ACF) and inter-aural cross-correlation function (IACF) were applied for analysis of the temporal and spatial properties of environmental noise. It was confirmed that the acoustical properties of aircraft noise and traffic noise are well described. These analyses provided useful parameters extracted from the ACF and IACF in assessing the subjective annoyance for noise. Thesis advisor: Yoichi Ando Copies of this thesis written in English can be obtained from Junko Atagi, 6813 Mosonou, Saijo-cho, Higashi-Hiroshima 739-0024, Japan. E-mail address: atagi\\@urban.ne.jp.

  10. Benefit of spatial filtering for visual perception with a subretinal implant.

    Science.gov (United States)

    Rieger, Viola; Aryan, Naser Pour; Brendler, Christian; Rothermel, Albrecht

    2014-01-01

    Subretinal implants have proven to be capable of restoring vision to patients suffering from hereditary retinal degeneration diseases like retinitis pigmentosa and cone-rod dystrophy. Although they already provide basic visual perception, there is still much room for improvement in this field. Effects like electric field interference limit the visual acuity and may be the cause of the perceived vision to be blurred. This influence could be reduced by means of highpass spatial filtering. In this paper, based on the available reports about the visual perception parameters from the patients using the alpha-IMS subretinal implant, a model for the blurring effect of the patients retina is proposed. On this basis, highpass filters are suggested which will compensate the obscuring effect of the stimulator device plus retina system to some extent.

  11. Technique originale de relèvement enclouage à foyer fermé d'une ...

    African Journals Online (AJOL)

    Le relèvement enclouage à foyer fermé (R.E.F.F) est une technique originale de traitement des fractures thalamiques du calcanéum. Il s'agit d'un patient âgé de 40 ans sans antécédents, victime d'une chute domestique sur le talon droit, d'une hauteur de 3 mètres. Le patient présentait un 'dème et une ecchymose du talon ...

  12. Cause rare d'une perforation de la cloison nasale

    Science.gov (United States)

    Jahidi, Ali; Hemmaoui, Bouchaïb; Itoua, Wulfran Rosaire; Errami, Noureddine; Benariba, Fouad

    2014-01-01

    Les perforations de la cloison nasale constituent une pathologie fréquente en ORL. Leurs causes sont multiples et restent dominées par les traumatismes chirurgicaux. Les étiologies infectieuses et notamment la tuberculose sont rares. Nous présentons le cas d'une patiente ayant bénéficié d'une méatotomie bilatérale et chez laquelle une perforation de la cloison nasale a été découverte lors d'un examen systématique à un an de son intervention. D'abord considérée comme une complication de la chirurgie, la biopsie des berges de la perforation a permis de déterminer son origine tuberculeuse. La présentation clinique des perforations de la cloison nasale n'est pas spécifique. Elles sont souvent asymptomatiques et de découverte fortuite. Les traumatismes notamment chirurgicaux sont le plus siuvent en cause. L′orogine tuberculeuse resta très rare. Le diagnostic de certitude de tuberculose repose sur la biopsie des berges de cette perforation. Le but de ce travail est de mettre en avant l'intérêt de la biopsie dans le diagnostic de la tuberculose de la cloison nasale. Cette biopsie doit être systématique même en cas d'antécédents de chirurgie endonasale qui est le plus souvent en cause dans les perforations de la cloison nasale. PMID:24932334

  13. Student perceptions and lessons learned from flipping a masters level public health course | Perceptions des étudiants et leçons tirées d’une classe inversée pour un cours de maîtrise en santé environnementale et professionnelle

    Directory of Open Access Journals (Sweden)

    Lindsay P. Galway

    2015-05-01

    Full Text Available The flipped classroom instructional model has emerged as an alternative to conventional lecture-based teaching that has dominated higher education for decades. In 2013, a cohort of graduate-level public health students participated in a flipped environmental and occupational health course. We present the design, implementation, and evaluation of this course. Using data collected from a post-course survey, focus group sessions, and classroom observation, we examine student perceptions of the flipped classroom instructional model and synthesize lessons learned from flipping the classroom more broadly. Post-course survey data indicate that students had generally positive perceptions towards the flipped classroom instructional model. Four major themes emerged from the focus group data in relation to perceptions of the flipped classroom: knowledge application, content delivery, innovation, and connecting the online and in-class components. These results are promising and suggest that this approach warrants further consideration and research. Le modèle pédagogique de la classe inversée a émergé comme solution de rechange à l’enseignement traditionnel par cours magistraux qui a dominé l’éducation supérieure pendant des décennies. En 2013, une cohorte d’étudiants en santé publique aux cycles supérieurs a participé à un cours inversé sur la santé environnementale et professionnelle. Nous présentons la conception, la mise en œuvre et l’évaluation de ce cours. À l’aide de données recueillies par l’entremise d’un sondage après le cours, lors de séances de discussion en groupe et d’observation en classe, nous examinons les perceptions qu’ont les étudiants du modèle pédagogique de la classe inversée et résumons les leçons tirées qui sont pertinentes pour les cours inversés en général. Les données du sondage réalisé après le cours indiquent que les étudiants avaient des perceptions pour la plupart

  14. Quel équilibre entre urbanisation et préservation des espaces agricoles périurbains ? Le cas d’une agglomération moyenne

    Directory of Open Access Journals (Sweden)

    José Serrano

    2005-11-01

    Full Text Available Le développement durable d'une ville conduit à remettre en cause l’étalement urbain. Aujourd'hui, les élus se vantent d’appliquer les principes du développement durable. Ils cherchent à préserver le cadre de vie et à maîtriser l'urbanisation. Pourtant, ces mêmes élus inscrivent dans les documents d'urbanisme des projets de développement ambitieux forts consommateurs d'espace. À travers une analyse des projets des élus de la ceinture périurbaine de Tours, il s'agit de déterminer la place qui est faite à la préservation des espaces ouverts. Nous analyserons quelles sont les conditions pour une reconnaissance des espaces agricoles et naturels comme étant un prolongement de la ville (et non plus l'absence de celle-ci. L’hypothèse est que la reconnaissance des espaces agricoles et naturels repose sur une modification de la perception de ces espaces. Mais face à l'ampleur des remises en cause que suppose cette évolution l'intervention d'un médiateur est nécessaire.Where is the balance between a town growth and the protection of agricultural per urban spaces ? The case of an average developed area. Urban sustainable development is in opposition with urban spraw. Today, elected officials speak big about the application of sustainable development principles. They are looking for preserving the setting and for controling the urban expansion. Nethertheless, the same elected officials create ambitious projects in urban planning documents. Through the analysis of elected officials developement projects, we’ll try to determine the importance of protecting natural spaces. The second objective is to know which are the conditions to recognize agricultural and natural spaces as an extention of the town (and not as the lack of it. Our hypothesis is that the recognition of farm land and natural spaces depends on a modification of the perception of the farmers’ role. But facing the extend of change regarding this evolution the

  15. Une-Mati lood vene keeles

    Index Scriptorium Estoniae

    2004-01-01

    Dagmar Normeti lasteraamatu "Une-Mati, Päris-Mati ja Tups" tõlget vene keelde (tõlkijad Irina Belobrovtseva ja Vitali Belobrovtsev; ill. Siima Shkop) esitletakse täna Kirjanike Liidu saalis; vt. ka Postimees, 19. märts, lk. 14

  16. Le pneumothorax spontané comme une manifestation évolutive de ...

    African Journals Online (AJOL)

    Le pneumothorax spontané comme une manifestation évolutive de la polyarthrite rhumatoide: à propos d'une observation clinique et revue de la litterature. Magaye Gaye, Assane Ndiaye, Mouhamed Lamine Fall, Souleymane Diatta, Papa Adama Dieng, Papa Salmane Ba, Amadou Gabriel Ciss, Mouhamadou Ndiaye ...

  17. Human factors involved in perception and action in a natural stereoscopic world: an up-to-date review with guidelines for stereoscopic displays and stereoscopic virtual reality (VR)

    Science.gov (United States)

    Perez-Bayas, Luis

    2001-06-01

    In stereoscopic perception of a three-dimensional world, binocular disparity might be thought of as the most important cue to 3D depth perception. Nevertheless, in reality there are many other factors involved before the 'final' conscious and subconscious stereoscopic perception, such as luminance, contrast, orientation, color, motion, and figure-ground extraction (pop-out phenomenon). In addition, more complex perceptual factors exist, such as attention and its duration (an equivalent of 'brain zooming') in relation to physiological central vision, In opposition to attention to peripheral vision and the brain 'top-down' information in relation to psychological factors like memory of previous experiences and present emotions. The brain's internal mapping of a pure perceptual world might be different from the internal mapping of a visual-motor space, which represents an 'action-directed perceptual world.' In addition, psychological factors (emotions and fine adjustments) are much more involved in a stereoscopic world than in a flat 2D-world, as well as in a world using peripheral vision (like VR, using a curved perspective representation, and displays, as natural vision does) as opposed to presenting only central vision (bi-macular stereoscopic vision) as in the majority of typical stereoscopic displays. Here is presented the most recent and precise information available about the psycho-neuro- physiological factors involved in the perception of stereoscopic three-dimensional world, with an attempt to give practical, functional, and pertinent guidelines for building more 'natural' stereoscopic displays.

  18. Visions of human futures in space and SETI

    Science.gov (United States)

    Wright, Jason T.; Oman-Reagan, Michael P.

    2018-04-01

    We discuss how visions for the futures of humanity in space and SETI are intertwined, and are shaped by prior work in the fields and by science fiction. This appears in the language used in the fields, and in the sometimes implicit assumptions made in discussions of them. We give examples from articulations of the so-called Fermi Paradox, discussions of the settlement of the Solar System (in the near future) and the Galaxy (in the far future), and METI. We argue that science fiction, especially the campy variety, is a significant contributor to the `giggle factor' that hinders serious discussion and funding for SETI and Solar System settlement projects. We argue that humanity's long-term future in space will be shaped by our short-term visions for who goes there and how. Because of the way they entered the fields, we recommend avoiding the term `colony' and its cognates when discussing the settlement of space, as well as other terms with similar pedigrees. We offer examples of science fiction and other writing that broaden and challenge our visions of human futures in space and SETI. In an appendix, we use an analogy with the well-funded and relatively uncontroversial searches for the dark matter particle to argue that SETI's lack of funding in the national science portfolio is primarily a problem of perception, not inherent merit.

  19. Rues en parallèle, une étude comparative entre Shanghai et Paris

    Directory of Open Access Journals (Sweden)

    Thierry Sanjuan

    2010-05-01

    Full Text Available Alors que les métropoles chinoises connaissent  une globalisation accélérée, l’observation de deux rues, l’une chinoise, l’autre parisienne,  aide à comprendre  ce qui  fait leur permanence et leur singularité, notamment les différences et les similitudes qui concernent les différents aspects de leur mutation. Ce sont en particulier  les caractéristiques  du processus de gentrification que ces deux rues connaissent qui les différencient: pour la rue du faubourg Saint Antoine domine une gentrification résidentielle, de type socio-culturelle, qui s’affirme depuis une trentaine d’année ; tandis que pour la rue Sichuan (Nord, on observe une gentrification de fréquentation, encouragée par une politique très volontaire de renforcement rapide de sa vocation commerciale à l’échelle métropolitaine au détriment des espaces et des populations riveraines.

  20. Case Report - Une tumeur exceptionnelle du doigt: la tumeur ...

    African Journals Online (AJOL)

    ... mous rend le diagnostic de ces tumeurs mésenchymateuses difficile et tardif. Dans 20à 30 % des cas le comportement de la TFS est celui d'une tumeur maligne localement agressive et récidivante, avec des métastases rares et tardives. Ce comportement impose une surveillance prolongée après exérèse chirurgicale.

  1. Ambiguities and conventions in the perception of visual art.

    Science.gov (United States)

    Mamassian, Pascal

    2008-09-01

    Vision perception is ambiguous and visual arts play with these ambiguities. While perceptual ambiguities are resolved with prior constraints, artistic ambiguities are resolved by conventions. Is there a relationship between priors and conventions? This review surveys recent work related to these ambiguities in composition, spatial scale, illumination and color, three-dimensional layout, shape, and movement. While most conventions seem to have their roots in perceptual constraints, those conventions that differ from priors may help us appreciate how visual arts differ from everyday perception.

  2. Cortical visual prostheses: from microstimulation to functional percept

    Science.gov (United States)

    Najarpour Foroushani, Armin; Pack, Christopher C.; Sawan, Mohamad

    2018-04-01

    Cortical visual prostheses are intended to restore vision by targeted electrical stimulation of the visual cortex. The perception of spots of light, called phosphenes, resulting from microstimulation of the visual pathway, suggests the possibility of creating meaningful percept made of phosphenes. However, to date electrical stimulation of V1 has still not resulted in perception of phosphenated images that goes beyond punctate spots of light. In this review, we summarize the clinical and experimental progress that has been made in generating phosphenes and modulating their associated perceptual characteristics in human and macaque primary visual cortex (V1). We focus specifically on the effects of different microstimulation parameters on perception and we analyse key challenges facing the generation of meaningful artificial percepts. Finally, we propose solutions to these challenges based on the application of supervised learning of population codes for spatial stimulation of visual cortex.

  3. Near vision spectacle coverage and barriers to near vision ...

    African Journals Online (AJOL)

    easily help to address this visual disability.7 An average cost of near vision spectacle in Ghana is approximately. $ 5.8 Near-vision spectacle could be dispensed as single vision, bifocal or progressive eye glasses to meet near vi- sion needs.2. Recent evidence suggests that the ageing population in. Ghana is increasing ...

  4. Performances d'une nouvelle approche dans l'estimation au champ

    African Journals Online (AJOL)

    ACSS

    Elle possède cependant des limitations, dues à l'organisation temporaire d'une .... Performances d'une nouvelle approche dans l'estimation au champ utilisant le principe de la ... différents types de résidus (soja, luzerne, haricot et maïs) et ...

  5. Adaptations respiratoires et circulatoires de l'esturgeon sibérien à une hypoxie environnementale

    Directory of Open Access Journals (Sweden)

    MAXIME V.

    1998-07-01

    Full Text Available Les adaptations respiratoires, acido-basiques et quelques effets circulatoires ont été étudiés chez l'esturgeon sibérien Acipenser baeri lors d'une hypoxie progressive ou d'un choc hypoxique, et du retour en normoxie. Au cours d'une hypoxie progressive, ce poisson est capable, en hyperventilant, de maintenir constante sa consommation d'oxygène jusqu'à une valeur critique de pression partielle d'oxygène dans l'eau située entre 20 et 40 mmHg. Le retour en normoxie est caractérisé par le paiement d'une dette d'oxygène, indiquant qu'un recours au métabolisme anaérobie a été nécessaire durant l'hypoxie. L'hypoxie progressive provoque initialement une alcalose ventilatoire associée ensuite à une acidose métabolique. Le choc hypoxique induit un état de stress comme en témoignent les valeurs élevées des taux plasmatiques de catécholamines. L'hyperventilation initiale est suivie d'une importante dépression ventilatoire. L'hypertension observée dans un premier temps, bien que modérée, représente un effet d'une augmentation du taux de catécholamines plasmatiques. Cet effet est ensuite atténué par une bradycardie d'origine vraisemblablement vagale, concomitante de l'hypoventilation. Les conséquences sur l'équilibre acido-basique, bien qu'amplifiées, sont comparables à celles d'une hypoxie progressive. Cependant, la libération très importante de lactate dans le sang lors du retour en normoxie n'entraîne qu'une faible diminution de pH du fait d'une augmentation concomitante du taux de sodium plasmatique. Ainsi l'esturgeon Acipenser baeri, bien que considéré comme un poisson archaïque, a développé les mêmes réponses adaptatives à l'hypoxie que les téléostéens.

  6. vision systématique des effets de la fréquence des repas en famille sur les résultats psychosociaux chez les jeunes

    Science.gov (United States)

    Harrison, Megan E.; Norris, Mark L.; Obeid, Nicole; Fu, Maeghan; Weinstangel, Hannah; Sampson, Margaret

    2015-01-01

    Résumé Objectif Effectuer unevision systématique des effets de repas en famille fréquents sur les résultats psychosociaux chez les enfants et les adolescents et examiner s’il existe des différences dans les résultats selon le sexe. Sources des données Des études ont été cernées à la suite d’une recherche dans MEDLINE (de 1948 à la dernière semaine de juin 2011) et dans PsycINFO (de 1806 à la première semaine de juillet 2011) à l’aide de l’interface Ovide. Les expressions et mots clés MeSH utilisés seuls ou en combinaisons étaient les suivants : family, meal, food intake, nutrition, diets, body weight, adolescent attitudes, eating behaviour, feeding behaviour et eating disorders. Les bibliographies des articles jugés pertinents ont aussi été passées en revus. Sélection des études La recherche initiale a produit 1783 articles. Pour être incluses dans l’analyse, les études devaient répondre aux critères suivants : être publiées en anglais dans une revue révisée par des pairs; porter sur des enfants ou des adolescents; traiter de l’influence des repas en famille sur les paramètres psychosociaux (p. ex. consommation de drogues et autres substances, troubles de l’alimentation, dépression) chez les enfants ou les adolescents; avoir une conception d’étude appropriée, notamment des méthodes statistiques acceptables pour l’analyse des paramètres. Quatorze articles satisfaisaient aux critères d’inclusion. Deux examinateurs indépendants ont étudié et analysé les articles. Synthèse Dans l’ensemble, les résultats font valoir que la fréquence des repas en famille est inversement proportionnelle aux troubles de l’alimentation, à la consommation d’alcool et de drogues, aux comportements violents, aux sentiments de dépression ou aux pensées suicidaires chez les adolescents. Il existe une relation positive entre de fréquents repas en famille, une bonne estime de soi et la réussite scolaire. Les

  7. Multisensory flavor perception.

    Science.gov (United States)

    Spence, Charles

    2015-03-26

    The perception of flavor is perhaps the most multisensory of our everyday experiences. The latest research by psychologists and cognitive neuroscientists increasingly reveals the complex multisensory interactions that give rise to the flavor experiences we all know and love, demonstrating how they rely on the integration of cues from all of the human senses. This Perspective explores the contributions of distinct senses to our perception of food and the growing realization that the same rules of multisensory integration that have been thoroughly explored in interactions between audition, vision, and touch may also explain the combination of the (admittedly harder to study) flavor senses. Academic advances are now spilling out into the real world, with chefs and food industry increasingly taking the latest scientific findings on board in their food design. Copyright © 2015 Elsevier Inc. All rights reserved.

  8. La culture, une arme de constructions massives.

    Directory of Open Access Journals (Sweden)

    Patrick Poncet

    2008-06-01

    Full Text Available Le recueil de texte que nous propose Jean-Michel Tobelem autour des questions de « diplomatie culturelle » peut être considéré comme un objet à double sens : une source et une exploration. Comme recueil de documents, le directeur d’ouvrage s’est attaché à réunir dans un volume somme toute restreint des contributions de spécialistes de divers sujets « culturels » à qui il était demandé de livrer leur savoir sous un angle valorisant le lien entre diplomatie et culture. ...

  9. Une frontière dans l’Europe.

    Directory of Open Access Journals (Sweden)

    Dominique Andrieu

    2005-07-01

    Full Text Available En l’espace d’une semaine, la France et la Suisse ont eu à se prononcer par référendum sur l’avenir de  leur pays dans l’Europe. L’un, en France le 29 mai 2005, portait sur l’adoption du traité constitutionnel et l’autre, la Suisse le 5 juin, portait sur leur entrée dans l’espace de Schengen. Bien que ces deux questions recouvrent deux définitions politiques et spatiales différentes, l’Union politique à 25 pour l’une et l’autre un traité à vocation politique ...

  10. Speed of vision depends on temporal expectancy

    DEFF Research Database (Denmark)

    Vangkilde, Signe Allerup; Bundesen, Claus

    2009-01-01

    (1.33 s-1) or low (0.22 s-1) corresponding to mean waiting times of 750 ms and 4,500 ms, respectively. The probability (p) of correct report was approximately an exponential function of the stimulus duration (t): p = 1 - exp[-v (t - t0)], where t0 measured the threshold of conscious perception, and v...... even though no general decrease in processing speed over time occurred; thus, the observed pattern was independent of the actual duration of the waiting time, but depended entirely on expectation. This seems to be the first time speed of vision - unconfounded by motor components - has been shown...

  11. Multiple episodes of convergence in genes of the dim light vision pathway in bats.

    Directory of Open Access Journals (Sweden)

    Yong-Yi Shen

    Full Text Available The molecular basis of the evolution of phenotypic characters is very complex and is poorly understood with few examples documenting the roles of multiple genes. Considering that a single gene cannot fully explain the convergence of phenotypic characters, we choose to study the convergent evolution of rod vision in two divergent bats from a network perspective. The Old World fruit bats (Pteropodidae are non-echolocating and have binocular vision, whereas the sheath-tailed bats (Emballonuridae are echolocating and have monocular vision; however, they both have relatively large eyes and rely more on rod vision to find food and navigate in the night. We found that the genes CRX, which plays an essential role in the differentiation of photoreceptor cells, SAG, which is involved in the desensitization of the photoactivated transduction cascade, and the photoreceptor gene RH, which is directly responsible for the perception of dim light, have undergone parallel sequence evolution in two divergent lineages of bats with larger eyes (Pteropodidae and Emballonuroidea. The multiple convergent events in the network of genes essential for rod vision is a rare phenomenon that illustrates the importance of investigating pathways and networks in the evolution of the molecular basis of phenotypic convergence.

  12. AN INVESTIGATION OF VISION PROBLEMS AND THE VISION CARE SYSTEM IN RURAL CHINA.

    Science.gov (United States)

    Bai, Yunli; Yi, Hongmei; Zhang, Linxiu; Shi, Yaojiang; Ma, Xiaochen; Congdon, Nathan; Zhou, Zhongqiang; Boswell, Matthew; Rozelle, Scott

    2014-11-01

    This paper examines the prevalence of vision problems and the accessibility to and quality of vision care in rural China. We obtained data from 4 sources: 1) the National Rural Vision Care Survey; 2) the Private Optometrists Survey; 3) the County Hospital Eye Care Survey; and 4) the Rural School Vision Care Survey. The data from each of the surveys were collected by the authors during 2012. Thirty-three percent of the rural population surveyed self-reported vision problems. Twenty-two percent of subjects surveyed had ever had a vision exam. Among those who self-reported having vision problems, 34% did not wear eyeglasses. Fifty-four percent of those with vision problems who had eyeglasses did not have a vision exam prior to receiving glasses. However, having a vision exam did not always guarantee access to quality vision care. Four channels of vision care service were assessed. The school vision examination program did not increase the usage rate of eyeglasses. Each county-hospital was staffed with three eye-doctors having one year of education beyond high school, serving more than 400,000 residents. Private optometrists often had low levels of education and professional certification. In conclusion, our findings shows that the vision care system in rural China is inadequate and ineffective in meeting the needs of the rural population sampled.

  13. L'industrialisation de l'exploitation de l'or à Kalsaka, Burkina Faso : une chance pour une population rurale pauvre ?

    Directory of Open Access Journals (Sweden)

    Matthieu Thune

    2011-09-01

    Full Text Available On assiste au Burkina Faso au passage d'une exploitation essentiellement artisanale de l'or à une exploitation industrielle. Sur des sites miniers exploités jusqu'alors de façon artisanale, l'arrivée d'une entreprise industrielle perturbe les rapports des habitants aux espaces qu’ils exploitent et aux bénéfices qu’ils prétendent en tirer. A travers l'étude du site de Kalsaka, au nord du pays, il s'agit d'analyser les changements engendrés par l'arrivée de la mine sur les activités rurales. L'implantation de l'entreprise minière bouleverse l’économie locale dans le sens d'une paupérisation et ne constitue pas une nouvelle opportunité économique pour les habitants du lieu. Toutefois, les acteurs locaux sont inégalement touchés et de nombreux habitants perturbés dans leurs activités ont été en mesure de s'adapter au changement.Burkina Faso is faced with the transition from a mainly traditional gold mining activity to an industrial one. On sites that had hitherto been mined with traditional techniques, the setting-up of an industrial company interferes with the way the population interact with the area, as well as the profit they wish to draw from it. The point of this study on the Kalsaka site, situated in the north of the country, is to analyze the impact the mine has caused on rural activities. The emergence of the mining company has impoverished the local economy and has failed to provide the local population with any new economic opportunity. However, the locals turned out to be unevenly affected and many people -whose activity had initially been disrupted- have adjusted to the change.

  14. Empty Quarter (Une Femme en Afrique de Raymond Depardon : l’image d’une voix off

    Directory of Open Access Journals (Sweden)

    Cyril Laverger

    2011-08-01

    Full Text Available Pour son premier long métrage de fiction, Raymond Depardon choisit un dispositif radical pour mettre en scène la passion amoureuse d’un homme pour une femme : ne jamais le voir ni l’entendre ; il est présent uniquement par sa voix off et les regards-caméra de cette femme. Une certaine forme de point de vue subjectif s’ancre dans les premières séquences. Pourtant, malgré une séquence en caméra portée épaule, des indices sonores et visuels troublent étrangement ce point de vue subjectif : un inattendu son interne objectif associé au personnage féminin et des questions posées au personnage-voix off restant sans réponse. Le spectateur est ainsi insensiblement amené à s’interroger sur le statut de cette voix off : temporalité variable, « dialogue improbable » entre voix off et voix in, existence même de ce personnage-voix off... Dans Empty Quarter, la voix off devient un véritable personnage relatant une histoire tout autant vécue que fantasmée.For his first fiction feature, Raymond Depardon chooses a radical device to direct the passionate love of a man for a woman: never see him never hear him; he is only present thanks to his voice-over and the camera-glances of this woman. Kind of a shape of a subjective point of view is anchored in the first sequences. Yet, despite a hand-held shot, sound and visual clues strangely disturb this subjective point of view; an unexpected objective internal sound linked to the female character and the questions asked to the voice-over-character remain unanswered. The audience is imperceptibly led to ask itself questions on the status of this voice-over: varying time-scale, « improbable dialogue » between voice-over and voice-in, mere existence of this voice over character... In Empty Quarter, the voice-over becomes a real character telling a story which is both lived and fantasized.

  15. vision quinquennale 2015 : la dernière ligne droite

    CERN Multimedia

    Staff Association

    2015-01-01

    Tous les cinq ans, les conditions financières et sociales des membres du personnel sont examinées selon la procédure définie dans l’Annexe A1 de nos Statut et Règlement du personnel (S&RP). Cet exercice est appelé « l’examen quinquennal » (5YR). Les résultats de cette révision doivent être connus fin 2015 pour une mise en œuvre à partir du 1er janvier 2016. Avant de commencer cet exercice, l’Association du personnel a interrogé en automne 2013 le personnel pour connaître ses préoccupations (voir aussi nos articles dans Écho n° 192 et 194). Les participants à l’enquête étaient invités à classer par ordre de priorité décroissant 15 thèmes.  La figure ci-dessous montre que la politique...

  16. Living with vision loss

    Science.gov (United States)

    Diabetes - vision loss; Retinopathy - vision loss; Low vision; Blindness - vision loss ... of visual aids. Some options include: Magnifiers High power reading glasses Devices that make it easier to ...

  17. La titrisation de la dette interieure de l'etat : une avenue prometteuse ...

    African Journals Online (AJOL)

    Une recension des écrits, non exhaustive mais assez suffisante a permis de relever, à travers cet article, que la titrisation est bien une stratégie de financement, qu'elle peut corriger les crises de liquidité et régler la dette nette. Elle a donc une utilité certaine pour les entreprises et les Etats en période de tension de trésorerie ...

  18. A child's vision.

    Science.gov (United States)

    Nye, Christina

    2014-06-01

    Implementing standard vision screening techniques in the primary care practice is the most effective means to detect children with potential vision problems at an age when the vision loss may be treatable. A critical period of vision development occurs in the first few weeks of life; thus, it is imperative that serious problems are detected at this time. Although it is not possible to quantitate an infant's vision, evaluating ocular health appropriately can mean the difference between sight and blindness and, in the case of retinoblastoma, life or death. Copyright © 2014 Elsevier Inc. All rights reserved.

  19. Basic quantitative assessment of visual performance in patients with very low vision.

    Science.gov (United States)

    Bach, Michael; Wilke, Michaela; Wilhelm, Barbara; Zrenner, Eberhart; Wilke, Robert

    2010-02-01

    A variety of approaches to developing visual prostheses are being pursued: subretinal, epiretinal, via the optic nerve, or via the visual cortex. This report presents a method of comparing their efficacy at genuinely improving visual function, starting at no light perception (NLP). A test battery (a computer program, Basic Assessment of Light and Motion [BaLM]) was developed in four basic visual dimensions: (1) light perception (light/no light), with an unstructured large-field stimulus; (2) temporal resolution, with single versus double flash discrimination; (3) localization of light, where a wedge extends from the center into four possible directions; and (4) motion, with a coarse pattern moving in one of four directions. Two- or four-alternative, forced-choice paradigms were used. The participants' responses were self-paced and delivered with a keypad. The feasibility of the BaLM was tested in 73 eyes of 51 patients with low vision. The light and time test modules discriminated between NLP and light perception (LP). The localization and motion modules showed no significant response for NLP but discriminated between LP and hand movement (HM). All four modules reached their ceilings in the acuity categories higher than HM. BaLM results systematically differed between the very-low-acuity categories NLP, LP, and HM. Light and time yielded similar results, as did localization and motion; still, for assessing the visual prostheses with differing temporal characteristics, they are not redundant. The results suggest that this simple test battery provides a quantitative assessment of visual function in the very-low-vision range from NLP to HM.

  20. Effects of visual skills training, vision coaching and sports vision ...

    African Journals Online (AJOL)

    The purpose of this study was to determine the effectiveness of three different approaches to improving sports performance through improvements in “sports vision:” (1) a visual skills training programme, (2) traditional vision coaching sessions, and (3) a multi-disciplinary approach identified as sports vision dynamics.

  1. Elevated arousal levels enhance contrast perception.

    Science.gov (United States)

    Kim, Dongho; Lokey, Savannah; Ling, Sam

    2017-02-01

    Our state of arousal fluctuates from moment to moment-fluctuations that can have profound impacts on behavior. Arousal has been proposed to play a powerful, widespread role in the brain, influencing processes as far ranging as perception, memory, learning, and decision making. Although arousal clearly plays a critical role in modulating behavior, the mechanisms underlying this modulation remain poorly understood. To address this knowledge gap, we examined the modulatory role of arousal on one of the cornerstones of visual perception: contrast perception. Using a reward-driven paradigm to manipulate arousal state, we discovered that elevated arousal state substantially enhances visual sensitivity, incurring a multiplicative modulation of contrast response. Contrast defines vision, determining whether objects appear visible or invisible to us, and these results indicate that one of the consequences of decreased arousal state is an impaired ability to visually process our environment.

  2. Role-play experience facilitates reading the mind of individuals with different perception.

    Directory of Open Access Journals (Sweden)

    Fumikazu Furumi

    Full Text Available The present study examined effects of role-play experience on reading the mind of people with different perception. It is normally difficult but very important in daily life to understand people with different characteristics, including those with restricted color vision. We explored the mechanisms of reading the mind of people with different perception. Forty university students were introduced to a communication task in which the use of mindreading was essential. During each trial, participants viewed a shelf, presented on a laptop computer, which contained several familiar objects, and they were instructed to touch an object on the shelf following an instruction issued by a partner who stood at the opposite side of the shelf. There were two partners: one was a monkey with normal color vision and the other was a dog with restricted color vision. The monkey could see all the objects in the same colors as the participants, whereas the dog saw some objects in different colors (e.g., he saw as yellow objects that the participants saw as red. Participants were required to respond according to the partner's instruction. In the restricted color vision condition, the dog saw the colors of objects differently; thus, participants had to work out his intentions (i.e., mind read, according to his different perspective. In the normal color vision condition, all objects were in the same colors as those seen by the monkey. Before the test phase, the role-play group had a role-play experience in which participants assumed the role of people with restricted color vision. No-role-play participants made significantly more errors in the restricted color vision condition than in the normal color vision condition, whereas among role-play participants, there was no difference between conditions. These results suggest that role-play experience facilitates reading the mind of people with perceptual experiences different from our own.

  3. Color vision test

    Science.gov (United States)

    ... present from birth) color vision problems: Achromatopsia -- complete color blindness , seeing only shades of gray Deuteranopia -- difficulty telling ... Vision test - color; Ishihara color vision test Images Color blindness tests References Bowling B. Hereditary fundus dystrophies. In: ...

  4. Impairments to Vision

    Science.gov (United States)

    ... an external Non-Government web site. Impairments to Vision Normal Vision Diabetic Retinopathy Age-related Macular Degeneration In this ... pictures, fixate on the nose to simulate the vision loss. In diabetic retinopathy, the blood vessels in ...

  5. Le syndrome de Budd-Chiari: une complication rare de la ...

    African Journals Online (AJOL)

    L'atteinte hépatique au cours de la sarcoïdose est une localisation fréquente, habituellement asymptomatique. La cholestase anictérique et l'hypertension portale représentent ses principales complications. Le syndrome de Budd-Chiari est une complication peu connue qui demeure exceptionnelle. Nous rapportons un ...

  6. Une proposition de nouveau cartogramme

    Directory of Open Access Journals (Sweden)

    Raymond Badel

    1990-05-01

    Full Text Available Le cartogramme proposé est une technique de recherche-exploration rapide grâce aux possibilités offertes par le micro-ordinateur et sa diffusion. La propriété foncière en vallée d'Aure lui sert de support.

  7. Visual motion perception predicts driving hazard perception ability.

    Science.gov (United States)

    Lacherez, Philippe; Au, Sandra; Wood, Joanne M

    2014-02-01

    To examine the basis of previous findings of an association between indices of driving safety and visual motion sensitivity and to examine whether this association could be explained by low-level changes in visual function. A total of 36 visually normal participants (aged 19-80 years) completed a battery of standard vision tests including visual acuity, contrast sensitivity and automated visual fields and two tests of motion perception including sensitivity for movement of a drifting Gabor stimulus and sensitivity for displacement in a random dot kinematogram (Dmin ). Participants also completed a hazard perception test (HPT), which measured participants' response times to hazards embedded in video recordings of real-world driving, which has been shown to be linked to crash risk. Dmin for the random dot stimulus ranged from -0.88 to -0.12 log minutes of arc, and the minimum drift rate for the Gabor stimulus ranged from 0.01 to 0.35 cycles per second. Both measures of motion sensitivity significantly predicted response times on the HPT. In addition, while the relationship involving the HPT and motion sensitivity for the random dot kinematogram was partially explained by the other visual function measures, the relationship with sensitivity for detection of the drifting Gabor stimulus remained significant even after controlling for these variables. These findings suggest that motion perception plays an important role in the visual perception of driving-relevant hazards independent of other areas of visual function and should be further explored as a predictive test of driving safety. Future research should explore the causes of reduced motion perception to develop better interventions to improve road safety. © 2012 The Authors. Acta Ophthalmologica © 2012 Acta Ophthalmologica Scandinavica Foundation.

  8. L'Afrique du Sud à la veille d'une consultation décisive

    NARCIS (Netherlands)

    Bayart, Jean François; Ellis, S.D.K.; Hibou, Béatrice

    1999-01-01

    En dépit de ses succès, le modèle démocratique sud-africain traverse une phase délicate. La succession du président Nelson Mandela annonce une possible crispation du pouvoir, en raison notamment des tendances autoritaires de Thabo Mbeki. Incapable de s'affirmer sur la scène continentale comme une

  9. L'infiltration d'une dilution ideale des solutions avec epineph rine au ...

    African Journals Online (AJOL)

    L'auteur rapporte un procédé simplifié de dilution d'une solution anesthésique avec épinéphrine passant d'une concentration de 1/100 000 à 1/800 000 pour rechercher une hémostase locale effective sans compromettre dans l'immédiat la vitalité de la vascularisation périphérique des lambeaux cutanés levés. The author ...

  10. Vision Lab

    Data.gov (United States)

    Federal Laboratory Consortium — The Vision Lab personnel perform research, development, testing and evaluation of eye protection and vision performance. The lab maintains and continues to develop...

  11. Le socle d'une œuvre, invisible mais essentiel

    OpenAIRE

    Huguenin, Daniel

    2015-01-01

    Tiré du site internet du blog des Musées d'art et d'histoire (http://blog.mahgeneve.ch): "Le support se faisant aujourd'hui le plus discret possible, voire invisible. Sa réalisation nécessite une étroite collaboration entre les différents acteurs d'une exposition car le socleur doit allier les besoins de la conservation et de la muséographie.".

  12. TERATOME MATURE DE LA PAROTIDE : A PROPOS D'UNE ...

    African Journals Online (AJOL)

    Le tératome de la parotide est une malformation tumorale vestigiale rare contenant des dérivés plus ou moins différenciés, des trois feuillets embryonnaires. A la lumière d'une nouvelle observation et des données de la littérature, on se propose de mettre l'accent sur les aspects cliniques, histologiques et thérapeutiques de ...

  13. Visual search in the real world: Color vision deficiency affects peripheral guidance, but leaves foveal verification largely unaffected

    Directory of Open Access Journals (Sweden)

    Günter eKugler

    2015-12-01

    Full Text Available Background: People with color vision deficiencies report numerous limitations in daily life. However, they use basic color terms systematically and in a similar manner as people with people with normal color vision. We hypothesize that a possible explanation for this discrepancy between color perception and behavioral consequences might be found in the gaze behavior of people with color vision deficiency.Methods: A group of participants with color vision deficiencies and a control group performed several search tasks in a naturalistic setting on a lawn.Results: Search performance was similar in both groups in a color-unrelated search task as well as in a search for yellow targets. While searching for red targets, color vision deficient participants exhibited a strongly degraded performance. This was closely matched by the number of fixations on red objects shown by the two groups. Importantly, once they fixated a target, participants with color vision deficiencies exhibited only few identification errors. Conclusions: Participants with color vision deficiencies are not able to enhance their search for red targets on a (green lawn by an efficient guiding mechanism. The data indicate that the impaired guiding is the main influence on search performance, while foveal identification (verification largely unaffected.

  14. Ageing vision and falls: a review.

    Science.gov (United States)

    Saftari, Liana Nafisa; Kwon, Oh-Sang

    2018-04-23

    Falls are the leading cause of accidental injury and death among older adults. One of three adults over the age of 65 years falls annually. As the size of elderly population increases, falls become a major concern for public health and there is a pressing need to understand the causes of falls thoroughly. While it is well documented that visual functions such as visual acuity, contrast sensitivity, and stereo acuity are correlated with fall risks, little attention has been paid to the relationship between falls and the ability of the visual system to perceive motion in the environment. The omission of visual motion perception in the literature is a critical gap because it is an essential function in maintaining balance. In the present article, we first review existing studies regarding visual risk factors for falls and the effect of ageing vision on falls. We then present a group of phenomena such as vection and sensory reweighting that provide information on how visual motion signals are used to maintain balance. We suggest that the current list of visual risk factors for falls should be elaborated by taking into account the relationship between visual motion perception and balance control.

  15. Vision after 53 years of blindness.

    Science.gov (United States)

    Sikl, Radovan; Simecček, Michal; Porubanová-Norquist, Michaela; Bezdíček, Ondřej; Kremláček, Jan; Stodůlka, Pavel; Fine, Ione; Ostrovsky, Yuri

    2013-01-01

    Several studies have shown that visual recovery after blindness that occurs early in life is never complete. The current study investigated whether an extremely long period of blindness might also cause a permanent impairment of visual performance, even in a case of adult-onset blindness. We examined KP, a 71-year-old man who underwent a successful sight-restoring operation after 53 years of blindness. A set of psychophysical tests designed to assess KP's face perception, object recognition, and visual space perception abilities were conducted six months and eight months after the surgery. The results demonstrate that regardless of a lengthy period of normal vision and rich pre-accident perceptual experience, KP did not fully integrate this experience, and his visual performance remained greatly compromised. This was particularly evident when the tasks targeted finer levels of perceptual processing. In addition to the decreased robustness of his memory representations, which was hypothesized as the main factor determining visual impairment, other factors that may have affected KP's performance were considered, including compromised visual functions, problems with perceptual organization, deficits in the simultaneous processing of visual information, and reduced cognitive abilities.

  16. Vision after 53 Years of Blindness

    Directory of Open Access Journals (Sweden)

    Radovan Šikl

    2013-12-01

    Full Text Available Several studies have shown that visual recovery after blindness that occurs early in life is never complete. The current study investigated whether an extremely long period of blindness might also cause a permanent impairment of visual performance, even in a case of adult-onset blindness. We examined KP, a 71-year-old man who underwent a successful sight-restoring operation after 53 years of blindness. A set of psychophysical tests designed to assess KP's face perception, object recognition, and visual space perception abilities were conducted six months and eight months after the surgery. The results demonstrate that regardless of a lengthy period of normal vision and rich pre-accident perceptual experience, KP did not fully integrate this experience, and his visual performance remained greatly compromised. This was particularly evident when the tasks targeted finer levels of perceptual processing. In addition to the decreased robustness of his memory representations, which was hypothesized as the main factor determining visual impairment, other factors that may have affected KP's performance were considered, including compromised visual functions, problems with perceptual organization, deficits in the simultaneous processing of visual information, and reduced cognitive abilities.

  17. Time Slices: What Is the Duration of a Percept?

    Directory of Open Access Journals (Sweden)

    Michael H Herzog

    2016-04-01

    Full Text Available We experience the world as a seamless stream of percepts. However, intriguing illusions and recent experiments suggest that the world is not continuously translated into conscious perception. Instead, perception seems to operate in a discrete manner, just like movies appear continuous although they consist of discrete images. To explain how the temporal resolution of human vision can be fast compared to sluggish conscious perception, we propose a novel conceptual framework in which features of objects, such as their color, are quasi-continuously and unconsciously analyzed with high temporal resolution. Like other features, temporal features, such as duration, are coded as quantitative labels. When unconscious processing is "completed," all features are simultaneously rendered conscious at discrete moments in time, sometimes even hundreds of milliseconds after stimuli were presented.

  18. Robot Vision Library

    Science.gov (United States)

    Howard, Andrew B.; Ansar, Adnan I.; Litwin, Todd E.; Goldberg, Steven B.

    2009-01-01

    The JPL Robot Vision Library (JPLV) provides real-time robot vision algorithms for developers who are not vision specialists. The package includes algorithms for stereo ranging, visual odometry and unsurveyed camera calibration, and has unique support for very wideangle lenses

  19. Visual perception and radiographic interpretation

    International Nuclear Information System (INIS)

    Papageorges, M.

    1998-01-01

    Although interpretation errors are common in radiology, their causes are still debated. Perceptual mechanisms appear to be responsible for a large proportion of mistakes made by both neophytes and trained radiologists. Erroneous perception of familiar contours can be triggered by unrelated opacities. Conversely, visual information cannot induce a specific perception if the observer is not familiar with the concept represented or its radiographicappearance. Additionally, the area of acute vision is smaller than is commonly recognized. Other factors, such as the attitude, beliefs,.: preconceptions, and expectations of the viewer, can affect what he or she ''sees'' whenviewing any object, including a radiograph. Familiarity with perceptual mechanisms and the limitations of the visual system as well as multiple readings may be necessary to reduce interpretation errors

  20. Edward Rhodes Stitt Award Lecture. Will a computer (with artificial vision) replace the surgical pathologist (or other health professionals)?

    Science.gov (United States)

    Heffner, D K

    1994-04-01

    Many jobs require vision for most of the tasks performed and the discussion focuses on the nature of human visual perception. Arguments are given to support the claim that visual perception is a very complicated function of the brain. To attempt to answer whether or not artificial intelligence (AI) will ever be able to essentially do what the brain does, the history and current state of AI research is examined, with special attention to neural net research.

  1. Une clinique possible avec les malades d’Alzheimer

    OpenAIRE

    Fontela, Cristina; Darnaud, Thierry

    2015-01-01

    Dans cet article les auteurs montrent qu’une psychothérapie d’inspiration psychanalytique est possible avec des sujets institutionnalisés présentant une démence du type Alzheimer. Elle se justifie d’autant plus que le sujet a subi des pertes relationnelles et d’objets libidinalement investis. Le clinicien tente de s’adapter à un psychisme en proie aux troubles cognitifs où les mouvements transféro-contretransférentiels sont massifs et ont un rôle particulier dans l’économie psychique du sujet...

  2. Audiovisual perception in amblyopia: A review and synthesis.

    Science.gov (United States)

    Richards, Michael D; Goltz, Herbert C; Wong, Agnes M F

    2018-05-17

    Amblyopia is a common developmental sensory disorder that has been extensively and systematically investigated as a unisensory visual impairment. However, its effects are increasingly recognized to extend beyond vision to the multisensory domain. Indeed, amblyopia is associated with altered cross-modal interactions in audiovisual temporal perception, audiovisual spatial perception, and audiovisual speech perception. Furthermore, although the visual impairment in amblyopia is typically unilateral, the multisensory abnormalities tend to persist even when viewing with both eyes. Knowledge of the extent and mechanisms of the audiovisual impairments in amblyopia, however, remains in its infancy. This work aims to review our current understanding of audiovisual processing and integration deficits in amblyopia, and considers the possible mechanisms underlying these abnormalities. Copyright © 2018. Published by Elsevier Ltd.

  3. Visions of Vision: An Exploratory Study of the Role College and University Presidents Play in Developing Institutional Vision

    Science.gov (United States)

    McWade, Jessica C.

    2014-01-01

    This qualitative research explores how college and university presidents engage in the process of developing formal institutional vision. The inquiry identifies roles presidents play in vision development, which is often undertaken as part of strategic-planning initiatives. Two constructs of leadership and institutional vision are used to examine…

  4. Production method of {alpha} particles; Une methode de production des particules {alpha}

    Energy Technology Data Exchange (ETDEWEB)

    Prevot, F [Commissariat a l' Energie Atomique, Saclay(France). Centre d' Etudes Nucleaires

    1953-07-01

    It is proposed a method to get an intense beam of {alpha} particles. With a source of ordinary ions, we form a helium beam, once ionized, it is accelerated with an energy of a few hundreds of keV. While crossing a matter any that can be a thin leaf or a gaseous blade, the second electron of helium is pulled with a yield that only depends on the energy of the beam of helium and that is equal to 1/2 for 650 keV. (author) [French] Il est propose une methode pour obtenir un faisceau intense de particules {alpha}. Avec une source d'ions ordinaire, on forme un faisceau d'helium une fois ionise qu'on accelere avec une energie de quelques centaines de keV. En traversant une matiere quelconque qui peut etre sous forme de feuille mince ou de lame gazeuse, le deuxieme electron de l'helium est arrache avec un rendement qui ne depend que de l'energie du faisceau d'helium et qui vaut 1/2 pour 650 keV. (auteur)

  5. Light Vision Color

    Science.gov (United States)

    Valberg, Arne

    2005-04-01

    Light Vision Color takes a well-balanced, interdisciplinary approach to our most important sensory system. The book successfully combines basics in vision sciences with recent developments from different areas such as neuroscience, biophysics, sensory psychology and philosophy. Originally published in 1998 this edition has been extensively revised and updated to include new chapters on clinical problems and eye diseases, low vision rehabilitation and the basic molecular biology and genetics of colour vision. Takes a broad interdisciplinary approach combining basics in vision sciences with the most recent developments in the area Includes an extensive list of technical terms and explanations to encourage student understanding Successfully brings together the most important areas of the subject in to one volume

  6. Signatures of functional constraint at aye-aye opsin genes: the potential of adaptive color vision in a nocturnal primate.

    Science.gov (United States)

    Perry, George H; Martin, Robert D; Verrelli, Brian C

    2007-09-01

    While color vision perception is thought to be adaptively correlated with foraging efficiency for diurnal mammals, those that forage exclusively at night may not need color vision nor have the capacity for it. Indeed, although the basic condition for mammals is dichromacy, diverse nocturnal mammals have only monochromatic vision, resulting from functional loss of the short-wavelength sensitive opsin gene. However, many nocturnal primates maintain intact two opsin genes and thus have dichromatic capacity. The evolutionary significance of this surprising observation has not yet been elucidated. We used a molecular population genetics approach to test evolutionary hypotheses for the two intact opsin genes of the fully nocturnal aye-aye (Daubentonia madagascariensis), a highly unusual and endangered Madagascar primate. No evidence of gene degradation in either opsin gene was observed for any of 8 aye-aye individuals examined. Furthermore, levels of nucleotide diversity for opsin gene functional sites were lower than those for 15 neutrally evolving intergenic regions (>25 kb in total), which is consistent with a history of purifying selection on aye-aye opsin genes. The most likely explanation for these findings is that dichromacy is advantageous for aye-ayes despite their nocturnal activity pattern. We speculate that dichromatic nocturnal primates may be able to perceive color while foraging under moonlight conditions, and suggest that behavioral and ecological comparisons among dichromatic and monochromatic nocturnal primates will help to elucidate the specific activities for which color vision perception is advantageous.

  7. What Is Low Vision?

    Science.gov (United States)

    ... Your Rights Training Resources Workplace Technology CareerConnect Stories Working as a Senior with Vision Loss For Seniors Age-Related Vision ... Changes Health and Aging Retirement Living Continuing to Work as a Senior with Vision Loss Get Connected About VisionAware Join ...

  8. Les faits,une arme contre

    International Development Research Centre (IDRC) Digital Library (Canada)

    un_focus_pauvreté. Aux Philippines, les progrès reposent sur une information rigoureuse. Aux Philippines, le système de suivi communautaire de la pauvreté, d'abord projet pilote, s'est étendu, en 14 ans, à l'échelle nationale, appuyé par tous les ordres ...

  9. Post-Secondary Educators’ Perceptions of Students’ Test Anxiety

    Directory of Open Access Journals (Sweden)

    Hannah A. Connon

    2016-06-01

    Full Text Available Student test anxiety (TA is a far-reaching concern in many post-secondary institutions as it can have a negative impact on student performance and retention. Educator perceptions of TA may influence the incidence of TA as well as treatment success. As such, we surveyed educators at a medium-sized Canadian university about their perceptions and experiences with TA. In total, 90% of surveyed educators (n=50 were willing to accommodate students with TA, and 69% of educators were aware of TA support services on campus, whereas only 40% could identify symptoms of TA. Two principal components were extracted from survey responses: the importance of TA on campus, and the importance of institutional commitment to managing TA. Perceived importance of TA varied by educator age and sex, with female and older educators perceiving TA as a more serious condition than male and younger educators. Educators that were aware of TA services had a more positive view of institutional commitment to TA. In addition, 42% of educators felt limited in their ability to assist students with TA, and only 40% believed their classes were structured in such a way as to minimize or address TA. Providing information to educators about the symptoms and treatability of TA, as well as available support services is recommended. L’anxiété des étudiants face aux examens est une préoccupation qui a des implications importantes dans de nombreux établissements d’enseignement post-secondaire car elle peut avoir des effets négatifs sur les résultats des étudiants et sur leur rétention. Les perceptions des éducateurs concernant l’anxiété face aux examens risquent d’influencer l’incidence de l’anxiété ainsi que la réussite du traitement. C’est pourquoi nous avons fait un sondage auprès d’éducateurs dans une université canadienne de taille moyenne à propos de leurs perceptions et de leurs expériences concernant l’anxiété face aux examens. Au total, 90

  10. Static and dynamic postural control in low-vision and normal-vision adults.

    Science.gov (United States)

    Tomomitsu, Mônica S V; Alonso, Angelica Castilho; Morimoto, Eurica; Bobbio, Tatiana G; Greve, Julia M D

    2013-04-01

    This study aimed to evaluate the influence of reduced visual information on postural control by comparing low-vision and normal-vision adults in static and dynamic conditions. Twenty-five low-vision subjects and twenty-five normal sighted adults were evaluated for static and dynamic balance using four protocols: 1) the Modified Clinical Test of Sensory Interaction on Balance on firm and foam surfaces with eyes opened and closed; 2) Unilateral Stance with eyes opened and closed; 3) Tandem Walk; and 4) Step Up/Over. The results showed that the low-vision group presented greater body sway compared with the normal vision during balance on a foam surface (p≤0.001), the Unilateral Stance test for both limbs (p≤0.001), and the Tandem Walk test. The low-vision group showed greater step width (p≤0.001) and slower gait speed (p≤0.004). In the Step Up/Over task, low-vision participants were more cautious in stepping up (right p≤0.005 and left p≤0.009) and in executing the movement (p≤0.001). These findings suggest that visual feedback is crucial for determining balance, especially for dynamic tasks and on foam surfaces. Low-vision individuals had worse postural stability than normal-vision adults in terms of dynamic tests and balance on foam surfaces.

  11. Foveal and peripheral fields of vision influences perceptual skill in anticipating opponents' attacking position in volleyball.

    Science.gov (United States)

    Schorer, Jörg; Rienhoff, Rebecca; Fischer, Lennart; Baker, Joseph

    2013-09-01

    The importance of perceptual-cognitive expertise in sport has been repeatedly demonstrated. In this study we examined the role of different sources of visual information (i.e., foveal versus peripheral) in anticipating volleyball attack positions. Expert (n = 11), advanced (n = 13) and novice (n = 16) players completed an anticipation task that involved predicting the location of volleyball attacks. Video clips of volleyball attacks (n = 72) were spatially and temporally occluded to provide varying amounts of information to the participant. In addition, participants viewed the attacks under three visual conditions: full vision, foveal vision only, and peripheral vision only. Analysis of variance revealed significant between group differences in prediction accuracy with higher skilled players performing better than lower skilled players. Additionally, we found significant differences between temporal and spatial occlusion conditions. Both of those factors interacted separately, but not combined with expertise. Importantly, for experts the sum of both fields of vision was superior to either source in isolation. Our results suggest different sources of visual information work collectively to facilitate expert anticipation in time-constrained sports and reinforce the complexity of expert perception.

  12. VISION development

    International Nuclear Information System (INIS)

    Hernandez, J.E.; Sherwood, R.J.; Whitman, S.R.

    1994-01-01

    VISION is a flexible and extensible object-oriented programming environment for prototyping computer-vision and pattern-recognition algorithms. This year's effort focused on three major areas: documentation, graphics, and support for new applications

  13. 2020 Vision Project Summary

    Energy Technology Data Exchange (ETDEWEB)

    Gordon, K.W.; Scott, K.P.

    2000-11-01

    Since the 2020 Vision project began in 1996, students from participating schools have completed and submitted a variety of scenarios describing potential world and regional conditions in the year 2020 and their possible effect on US national security. This report summarizes the students' views and describes trends observed over the course of the 2020 Vision project's five years. It also highlights the main organizational features of the project. An analysis of thematic trends among the scenarios showed interesting shifts in students' thinking, particularly in their views of computer technology, US relations with China, and globalization. In 1996, most students perceived computer technology as highly beneficial to society, but as the year 2000 approached, this technology was viewed with fear and suspicion, even personified as a malicious, uncontrollable being. Yet, after New Year's passed with little disruption, students generally again perceived computer technology as beneficial. Also in 1996, students tended to see US relations with China as potentially positive, with economic interaction proving favorable to both countries. By 2000, this view had transformed into a perception of China emerging as the US' main rival and ''enemy'' in the global geopolitical realm. Regarding globalization, students in the first two years of the project tended to perceive world events as dependent on US action. However, by the end of the project, they saw the US as having little control over world events and therefore, we Americans would need to cooperate and compromise with other nations in order to maintain our own well-being.

  14. Vision related quality of life in patients with type 2 diabetes in the EUROCONDOR trial.

    Science.gov (United States)

    Trento, Marina; Durando, Olga; Lavecchia, Sonia; Charrier, Lorena; Cavallo, Franco; Costa, Miguel Angelo; Hernández, Cristina; Simó, Rafael; Porta, Massimo

    2017-07-01

    To evaluate vision related quality of life in the patients enrolled in The European Consortium for the Early Treatment of Diabetic Retinopathy, a clinical trial on prevention of diabetic retinopathy. Four-hundred-forty-nine patients, 153 women, with type 2 Diabetes and no or mild diabetic retinopathy were enrolled in a 2-year multicenter randomized controlled trial. The 25-item National Eye Institute Visual Functioning Questionnaire was used to explore 12 subscales of vision related quality of life. The patients were 62.8 ± 6.7 years old and had 11.1 ± 5.6 years known disease duration. Diabetic retinopathy was absent in 193 (43.0 %) and mild in 256 (57.0 %). Patients without diabetic retinopathy were older, had shorter diabetes duration and used less insulin and glucose-lowering agents but did not differ by gender, best corrected visual acuity or any subscale, except vision specific mental health and vision specific role difficulties. Patients with reduced retinal thickness at the ganglion cell layer (n = 36) did not differ for diabetic retinopathy but were older, had lower best corrected visual acuity and worse scores for ocular pain, color vision and peripheral vision. On multivariable analysis, worse scores for general vision remained associated with reduced retinal thickness, diabetes duration and best corrected visual acuity, and scores for visual specific mental health with diabetic retinopathy and lower best corrected visual acuity. Visual specific role difficulties were only associated with reduced best corrected visual acuity. Scores for driving decreased among females, with worsening of Hemoglobin A1c and best corrected visual acuity. Color vision depended only on reduced retinal thickness, and peripheral vision on both reduced thickness and best corrected visual acuity. The National Eye Institute Visual Functioning Questionnaire could detect subtle changes in patients' perception of visual function, despite absent/minimal diabetic

  15. Seeing the Light: Optics in Nature, Photography, Color, Vision, and Holography

    Science.gov (United States)

    Falk, David R.; Brill, Dieter R.; Stork, David G.

    1985-11-01

    The most complete and lucid nonmathematical study of light available. Chapters are self-contained, making the book flexible and easy to read. Coverage includes such non-traditional topics as processes of vision and the eye, atmospherical optical phenomena, color perception and illusions, color in nature and in art, Kirilian photography, and holography. Includes experiments that can be carried out with simple equipment. Chapters contain optional advanced sections, and appendixes review the mathematics for quantitative aspects. Illustrated, including a four-color insert.

  16. Interaction between Olfaction and Gustation by Using Synchrony Perception Task

    Directory of Open Access Journals (Sweden)

    Tatsu Kobayakawa

    2011-10-01

    Full Text Available It seems that interaction between olfaction (smell sensation and gustation (taste sensation will stronger than other interactions among five senses, although no one has ever confirmed psychophysically. In this study, we utilized synchrony perception task to confirm this specificity comparing control condition, interaction between vision and olfaction and one between vision and gustation. We used NaCl as taste stimuli and flavor from bubbling chicken stock as olfactory stimuli. We used taste stimulator which was able to present pure gustation without tactile stimuli, and smell stimulator with original developed real time stimulus monitoring. We used LED for vision stimuli. Timing of both stimuli was shifted from −1000 ms to +1000ms with each other, and participants were instructed to judge synchronicity. Control conditions revealed that olfaction and gustation has almost equivalent temporal resolution to other sensations. And probability distribution between olfaction and gustation was quite different from other interactions including vision. These results shows interaction between olfaction and gustation is more specific.

  17. Création d’une aire protégée et logiques d’action de l’état et du milieu : analyse d’une irréconciabilité constructive à l’œuvre

    Directory of Open Access Journals (Sweden)

    Marie Lequin

    2011-08-01

    Full Text Available Cet article analyse les interactions socioculturelles d’acteurs multiples ayant des intérêts divergents en regard de la reconnaissance d’un espace naturel à titre d’aire protégée, plus particulièrement le Parc marin du Saguenay–Saint-Laurent (PMSSL, situé au Québec à l’embouchure de la rivière Saguenay. Compris dans le sens d’espace socialisé et investi de valeurs parfois contradictoires, ce territoire constitue le cas empirique sur lequel repose l’analyse des logiques d’acteurs. La perspective ici mise de l’avant repose à la fois sur une décision de l’État de créer et de mettre en valeur une aire marine ainsi que sur la participation active des collectivités territoriales dans la gestion du patrimoine environnemental et culturel lié à leur identité propre. Si la participation des communautés locales apparaît comme un élément essentiel et démocratique dans la reconnaissance d’un espace naturel protégé, il apparaît tout aussi capital de bien saisir la logique qui sous-tend les actions de l’État et du milieu. Les résultats empiriques montrent deux logiques d’action distinctes à l’œuvre, une logique classique de planification et implantation stratégique de l’état réservant une espace de participation programmée pour la communauté et une logique stratégique communautaire à caractère émergent, de portée moins englobante mais adaptable aux nouvelles réalités et contraintes gouvernementales. Les résultats peuvent être représentés sous forme d’un processus de gouvernance à l’œuvre, un caractérisé par une participation de base, mais un qui suggère qu’un processus plus hautement démocratique nécessiterait un plus haut degré de vigilance dans la perspective communautaire, suffisante pour produire une meilleure symétrie de pouvoir démocratique entre l’État.This paper analyzes the socio-cultural dynamic between multiple stakeholders with divergent interests

  18. La disponibilité temporelle au travail des femmes : une disponibilité sans contrepartie ? Women’s temporal availability at work : no compensation ?

    Directory of Open Access Journals (Sweden)

    François-Xavier Devetter

    2009-06-01

    Full Text Available Cet article s’appuie sur une vision enrichie du temps de travail (la disponibilité temporelle au travail, incluant la durée, la localisation et la prévisibilité des horaires pour étudier les différences de valorisation des contraintes temporelles entre hommes et femmes. Il apparaît que, certes, les femmes semblent avoir une disponibilité au travail plus réduite (notamment en début de carrière mais surtout que les écarts entre genres ne portent pas sur les mêmes dimensions du temps. La reconnaissance sociale (notamment par l’employeur des contraintes touchant les femmes semble bien plus faible que dans le cas des hommes.This article uses a broader concept of working time than mere duration (time availability at work encompassing the volume of hours worked but also the scheduling and predictability of those hours, to examine the gender gap concerning temporal constraints. Women seem to dispose of fewer possibilities to make themselves available at work than men but, more importantly, this gap does not involve the same aspects of time. The temporal constraints experienced mainly by women are less socially visible and hence undervalued by their employers.

  19. Localisation d'une source sonore par un réseau de microphones

    OpenAIRE

    Thaljaoui , Adel; Brulin , Damien; Val , Thierry; Nasri , Nejah

    2014-01-01

    National audience; L'assistance à domicile d'une personne âgée, notamment la connaissance de sa position géographique en tout instant, est devenue actuellement l'une des problématiques les plus urgentes. L'exploitation de l'information audio captée par un réseau de capteurs munis de microphones constitue un axe de recherche prometteur qui pourrait contribuer à une meilleure localisation dans le cadre des maisons intelligentes. Nous introduisons, dans cet article, nos premiers travaux sur la l...

  20. Quand la biopsie cutanée peut étiqueter une épilepsie | Harmouch ...

    African Journals Online (AJOL)

    La maladie de Lafora (ML) représente une forme rare et grave d'épilepsie myoclonique progressive. C'est une affection à transmission autosomique récessive, hétérogène sur le plan génétique. Nous rapportons le cas d'une adolescente de 16 ans, issue de parents consanguins de premier degré, qui présente depuis l'âge ...

  1. Vision-based interaction

    CERN Document Server

    Turk, Matthew

    2013-01-01

    In its early years, the field of computer vision was largely motivated by researchers seeking computational models of biological vision and solutions to practical problems in manufacturing, defense, and medicine. For the past two decades or so, there has been an increasing interest in computer vision as an input modality in the context of human-computer interaction. Such vision-based interaction can endow interactive systems with visual capabilities similar to those important to human-human interaction, in order to perceive non-verbal cues and incorporate this information in applications such

  2. Une Analyse de film pour comprendre le racisme

    OpenAIRE

    Rosiejka, Veronica Ann

    2014-01-01

    Il y a une nouvelle vague de racisme ouvert en France. Cependant, c'est un phénomène avec des racines sociales et historiques complexes. Ce mémoire cherche à comprendre le racisme de deux manières : généralement, aussi bien que spécifiquement à la France. Le centre d'attention principal de cette étude est la psychologie du racisme, comment le racisme fonctionne et ses conséquences, éléments qui sont étudiés à travers l'analyse d'une série de neuf courts-métrages,...

  3. Vision related quality of life in patients with type 2 diabetes in the EUROCONDOR trial

    DEFF Research Database (Denmark)

    Trento, Marina; Durando, Olga; Lavecchia, Sonia

    2017-01-01

    To evaluate vision related quality of life in the patients enrolled in The European Consortium for the Early Treatment of Diabetic Retinopathy, a clinical trial on prevention of diabetic retinopathy. Four-hundred-forty-nine patients, 153 women, with type 2 Diabetes and no or mild diabetic retinop...... acuity. The National Eye Institute Visual Functioning Questionnaire could detect subtle changes in patients' perception of visual function, despite absent/minimal diabetic retinopathy.......To evaluate vision related quality of life in the patients enrolled in The European Consortium for the Early Treatment of Diabetic Retinopathy, a clinical trial on prevention of diabetic retinopathy. Four-hundred-forty-nine patients, 153 women, with type 2 Diabetes and no or mild diabetic....... Diabetic retinopathy was absent in 193 (43.0 %) and mild in 256 (57.0 %). Patients without diabetic retinopathy were older, had shorter diabetes duration and used less insulin and glucose-lowering agents but did not differ by gender, best corrected visual acuity or any subscale, except vision specific...

  4. Maladie de Horton révélée par une dyspnée

    Science.gov (United States)

    Mahfoudhi, Madiha; Mamlouk, Habiba; Turki, Sami; Kheder, Adel

    2015-01-01

    Les manifestations pleuro-pulmonaires de la maladie de Horton sont rares et peu connues. Elles peuvent être inaugurales, à l'origine d'un retard à la prise en charge si elles sont méconnues. Il s'agissait d'un patient âgé de 75 ans, admis pour une dyspnée, une toux chronique et une fièvre. Il a reçu une antibiothérapie et a bénéficié d'une fibroscopie bronchique avec lavage broncho-alvéolaire à la recherche d'un germe, qui a révélé plutôt, une alvéolite lymphocytaire. L’évolution était marquée par la persistance des signes cliniques et du syndrome inflammatoire biologique. Un angio-scanner thoracique et une échographie cardiaque étaient sans anomalies. Une origine cardiaque, musculaire, hématologique, néoplasique, vasculaire ou métabolique de la dyspnée a été éliminée. Une maladie de Horton a été évoquée. La biopsie de l'artère temporale a confirmé le diagnostic d'une maladie de Horton. L’évolution sous corticothérapie était marquée par la disparition des signes cliniques et biologiques. Les manifestations pleuro-pulmonaires au cours de la maladie de Horton sont rares, et classiquement, rarement révélatrices de la maladie. La dyspnée peut initialement égarer le diagnostic vers d'autres étiologies notamment infectieuses. Le but de ce travail est d'insister sur le fait que la connaissance de ces différentes manifestations respiratoires au cours de la maladie de Horton (toux persistante, dyspnée, épanchement pleural) est utile au clinicien afin de prescrire une corticothérapie, chez un sujet le plus souvent âgé ayant un état fébrile et inflammatoire prolongé, permettant ainsi d’éviter l'apparition de complications. PMID:26161171

  5. Généalogie du concept d’assimilation. Une comparaison franco-britannique

    Directory of Open Access Journals (Sweden)

    Abdellali Hajjat

    2011-07-01

    Full Text Available Malgré la popularité du concept d’assimilation en sciences sociales, on connaît finalement peu de chose sur son origine intellectuelle. Cet article vise à faire la généalogie de ce concept dans une perspective franco-britannique. Sa traduction du latin vers le français et l’anglais conserve la signification de « similitude » mais le concept se sécularise, d’une part, à travers le langage des sciences naturelles dont l’influence favorise une réappropriation pour décrire les relations humaines et, d’autre part, le discours historique anglais et le discours politique colonial français. Dans le contexte britannique, l’assimilation devient une qualité collective attribuée à tout un peuple, puis utilisée en naturalisant les différences entre les peuples pour les rendre irréductibles et enfin s’enrichit d’une acception administrative. En France, la politisation du concept d’assimilation dans les discours et réglementations coloniaux provoque un bouleversement sémantique qui l’associe au concept d’égalité.

  6. Enhancing Motion-In-Depth Perception of Random-Dot Stereograms.

    Science.gov (United States)

    Zhang, Di; Nourrit, Vincent; De Bougrenet de la Tocnaye, Jean-Louis

    2018-07-01

    Random-dot stereograms have been widely used to explore the neural mechanisms underlying binocular vision. Although they are a powerful tool to stimulate motion-in-depth (MID) perception, published results report some difficulties in the capacity to perceive MID generated by random-dot stereograms. The purpose of this study was to investigate whether the performance of MID perception could be improved using an appropriate stimulus design. Sixteen inexperienced observers participated in the experiment. A training session was carried out to improve the accuracy of MID detection before the experiment. Four aspects of stimulus design were investigated: presence of a static reference, background texture, relative disparity, and stimulus contrast. Participants' performance in MID direction discrimination was recorded and compared to evaluate whether varying these factors helped MID perception. Results showed that only the presence of background texture had a significant effect on MID direction perception. This study provides suggestions for the design of 3D stimuli in order to facilitate MID perception.

  7. L’action française: une matrice européenne et transatlantique des droites radicales?

    Directory of Open Access Journals (Sweden)

    Olivier DARD

    2013-05-01

    Full Text Available L’action française et le maurrassisme sont indissociables de la figure de maurras. En même temps, ils la dépassent. L’action française renvoie à une réalité polymorphe articulée autour de trois piliers: une doctrine, un quotidien et une ligue. Cet ensemble a eu une influence incontestable non seulement en France mais aussi à l’étranger. Une étude sur ce dernier point permet de mettre en lumière une chronologie sensiblement différente de celle qui a été proposée pour la France. En même temps, l’examen des vecteurs de pénétration et des transferts politiques et culturels à l’œuvre font découvrir les différentes façons d’être maurrassien de l’Europe aux Amériques.

  8. Human perception and the uncertainty principle

    International Nuclear Information System (INIS)

    Harney, R.C.

    1976-01-01

    The concept of the uncertainty principle that position and momentum cannot be simultaneously specified to arbitrary accuracy is somewhat difficult to reconcile with experience. This note describes order-of-magnitude calculations which quantify the inadequacy of human perception with regards to direct observation of the breakdown of the trajectory concept implied by the uncertainty principle. Even with the best optical microscope, human vision is inadequate by three orders of magnitude. 1 figure

  9. L’UTOPIE – UNE FANTAISIE COMEPENSATOIRE ?

    Directory of Open Access Journals (Sweden)

    Ilinca BĂLAȘ

    2013-11-01

    Full Text Available La création du mot utopie n’est pas seulement l’acte de naissance d’un genre littéraire - le genre utopique, mais aussi la source d'une approche possible de l'utopie en tant que fantaisie compensatoire, à la suite du rapprochement entre le néologisme en linguistique et le néologisme en psychiatrie. Moyennant les concepts psychanalytiques de compensation et de régression, l'utopie pourrait être considérée soit comme une solution soit pour échapper à un complexe d'infériorité émanant d'un présent jugé comme insatisfaisant, soit comme un retour à des temps bienheureux de l'humanité. Dans les deux cas, la question angoissante qui en découle est si l’utopie relève du rêve ou bien plutôt du cauchemar.

  10. 94 Mise en place d'une base de données pour une modélisation ...

    African Journals Online (AJOL)

    AKA BOKO

    L'objectif de cette étude est de fournir les paramètres physiques du bassin versant ... certains procèdent par une approche globale et considère le bassin comme ... du Bandama, à l'instar de la plupart des bassins sub-sahéliens, ne dispose.

  11. Caractérisations physico-chimiques et microbiologiques d'une pate ...

    African Journals Online (AJOL)

    Gowé est une pâte fermentée obtenue à base de maïs pré-germé. Il est généralement consommé, après dilution, dans l'eau sous forme de boisson par une importante couche de nos populations aussi bien en milieu rural qu'urbain. Aussi, les conditions de sa production restent-elles toujours traditionnelles et très peu ...

  12. Secteur informel, climat des affaires et croissance économique : une ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Le caractère nébuleux de ces entreprises rend également difficile une taxation appropriée, ce qui fausse le jeu de la concurrence et pénalise les entreprises constituées en bonne et due forme. Le projet se propose de faire la lumière sur la diversité des types d'entreprises informelles au moyen d'une analyse des données ...

  13. Traitement chirurgical d'une luxation palmaire carpo-métacarpienne ...

    African Journals Online (AJOL)

    Les luxations carpo-métacarpiennes sont des lésions rares, les auteurs rapportent un cas de luxation carpo-métacarpienne palmaire du cinquième doigt, traité en urgence par réduction et stabilisation par embrochage à foyer fermé. Une immobilisation postopératoire par une attelle intrinsèque plus a été réalisée pendant ...

  14. Women and the vision thing.

    Science.gov (United States)

    Ibarra, Herminia; Obodaru, Otilia

    2009-01-01

    Are women rated lower than men in evaluations of their leadership capabilities because of lingering gender bias? No, according to an analysis of thousands of 360-degree assessments collected by Insead's executive education program. That analysis showed that women tend to outshine men in all areas but one: vision. Unfortunately, that exception is a big one. At the top tiers of management, the ability to see opportunities, craft strategy based on a broad view of the business, and inspire others is a must-have. To explore the nature of the deficit, and whether it is a perception or reality, Insead professor Ibarra and doctoral candidate Obodaru interviewed female executives and studied the evaluation data. They developed three possible explanations. First, women may do just as much as men to shape the future but go about it in a different way; a leader who is less directive, includes more people, and shares credit might not fit people's mental model of a visionary. Second, women may believe they have less license to go out on a limb. Those who have built careers on detail-focused, shoulder-to-the-wheel execution may hesitate to stray from facts into unprovable assertions about the future. Third, women may choose not to cultivate reputations as big visionaries. Having seen bluster passed off as vision, they may dismiss the importance of selling visions. The top two candidates for the Democratic nomination for U.S. president in 2008 offer an instructive parallel. The runner-up, Hillary Clinton, was viewed as a get-it-done type with an impressive, if uninspiring, grasp of policy detail. The winner, Barack Obama, was seen as a charismatic visionary offering a hopeful, if undetailed, future. The good news is that every dimension of leadership is learned, not inborn. As more women become skilled at, and known for, envisioning the future, nothing will hold them back.

  15. Optic ataxia and the function of the dorsal stream: contributions to perception and action.

    Science.gov (United States)

    Pisella, Laure; Sergio, Lauren; Blangero, Annabelle; Torchin, Héloïse; Vighetto, Alain; Rossetti, Yves

    2009-12-01

    Optic ataxia (OA) is one of the symptoms pertaining to Bálint's Syndrome. It has been described clinically for nearly 80 years before it became a cornerstone of the most popular dual stream theory of the visual brain. Over the last 10 years a regain of interest for this neurological condition lead to a number of precise analyses of the deficits found in optic ataxia, giving rise to a renewed outline of its very definition and hence of the function(s) of the occipito-parietal (dorsal) stream. In absence of concomitant clinical symptoms, we review evidence that misreaching errors in central vision result from the "hand effect": an erroneous dynamic spatial processing of proprioceptive information from the hand. When visual feedback of the hand is provided (closed-loop condition), pure optic ataxia is restricted to peripheral vision. This central versus peripheral vision distinction is repeatedly used to argue that action and perception are not unique and dissociated systems. New assessments of optic ataxia patients are provided, confirming on one hand that their visuomotor deficit is specific to peripheral vision (i.e. when the gaze and the hand goals are dissociated), on the other hand that they disclose perceptual deficits in peripheral vision. These results are coherent with the recent demonstration that optic ataxia patients exhibit a general contralesional deficit for dynamic visuo-spatial processing, affecting both hand and eye movements [Gaveau, V., Pélisson, D., Blangero, A., Urquizar, C., Prablanc, C.,Vighetto, A., et al. (2008). A common parietal module for saccade and reach: Eye-hand coordination and saccadic control in optic ataxia. Neuropsychologia, 46, 475-486]. Such module(s) within the dorsal stream could be used for both action and perception in the periphery. It is concluded that optic ataxia cannot be considered as a unitary and specific visuo-manual deficit, and that the modular organisation of the dorsal stream allows for numerous dorsal

  16. On the functional relevance of frontal cortex for passive and voluntarily controlled bistable vision.

    Science.gov (United States)

    de Graaf, Tom A; de Jong, Maartje C; Goebel, Rainer; van Ee, Raymond; Sack, Alexander T

    2011-10-01

    In bistable vision, one constant ambiguous stimulus leads to 2 alternating conscious percepts. This perceptual switching occurs spontaneously but can also be influenced through voluntary control. Neuroimaging studies have reported that frontal regions are activated during spontaneous perceptual switches, leading some researchers to suggest that frontal regions causally induce perceptual switches. But the opposite also seems possible: frontal activations may themselves be caused by spontaneous switches. Classically implicated in attentional processes, these same regions are also candidates for the origins of voluntary control over bistable vision. Here too, it remains unknown whether frontal cortex is actually functionally relevant. It is even possible that spontaneous perceptual switches and voluntarily induced switches are mediated by the same top-down mechanisms. To directly address these issues, we here induced "virtual lesions," with transcranial magnetic stimulation, in frontal, parietal, and 2 lower level visual cortices using an established ambiguous structure-from-motion stimulus. We found that dorsolateral prefrontal cortex was causally relevant for voluntary control over perceptual switches. In contrast, we failed to find any evidence for an active role of frontal cortex in passive bistable vision. Thus, it seems the same pathway used for willed top-down modulation of bistable vision is not used during passive bistable viewing.

  17. Quand la biopsie cutanée peut étiqueter une épilepsie

    Science.gov (United States)

    Harmouch, Taoufiq; Gallouj, Salim; Znati, Kaoutar; Sennou, Aicha Slassi; Belahcen, Faouzi; Amarti, Afaf

    2011-01-01

    La maladie de Lafora (ML) représente une forme rare et grave d’épilepsie myoclonique progressive. C'est une affection à transmission autosomique récessive, hétérogène sur le plan génétique. Nous rapportons le cas d'une adolescente de 16 ans, issue de parents consanguins de premier degré, qui présente depuis l’âge de 14 ans des crises d’épilepsie et des myoclonies. L'examen neurologique a montré un syndrome cérébelleux et une détérioration intellectuelle. La biopsie cutanée était indispensable pour orienter le diagnostic. La ML a un pronostic constamment fatal. L’étude histologique confirme le diagnostic et l’étude moléculaire peut aider à établir un conseil génétique. PMID:22187608

  18. Progress in computer vision.

    Science.gov (United States)

    Jain, A. K.; Dorai, C.

    Computer vision has emerged as a challenging and important area of research, both as an engineering and a scientific discipline. The growing importance of computer vision is evident from the fact that it was identified as one of the "Grand Challenges" and also from its prominent role in the National Information Infrastructure. While the design of a general-purpose vision system continues to be elusive machine vision systems are being used successfully in specific application elusive, machine vision systems are being used successfully in specific application domains. Building a practical vision system requires a careful selection of appropriate sensors, extraction and integration of information from available cues in the sensed data, and evaluation of system robustness and performance. The authors discuss and demonstrate advantages of (1) multi-sensor fusion, (2) combination of features and classifiers, (3) integration of visual modules, and (IV) admissibility and goal-directed evaluation of vision algorithms. The requirements of several prominent real world applications such as biometry, document image analysis, image and video database retrieval, and automatic object model construction offer exciting problems and new opportunities to design and evaluate vision algorithms.

  19. How to reduce the petroleum dependency of Quebec? A ground breaking collective approach; Comment reduire la dependance quebecoise au petrole? Une demarche collective inedite

    Energy Technology Data Exchange (ETDEWEB)

    Bourke, Philippe; Caron-Malenfant, Julie

    2010-09-15

    Quebec population and socio economic agents are little or not summoned to in the definition of a vision relating to the dependency of Quebec to petroleum. The presented approach expects to include them as determining actors in the research for solutions to this collective issue, exploring aspects linked both to the energy consumption and production. The question to which the consultation is looking for answers is: How can Quebec reduce its petroleum consumption and increase its energy independence while promoting the harmonious economic and social development of its territory?. [French] La population et les agents socioeconomiques du Quebec sont peu ou pas interpelles dans la definition d'une vision entourant la dependance du Quebec au petrole. La demarche presentee prevoit les inclure comme acteurs determinants vers la recherche de solutions a cet enjeu collectif, explorant les aspects lies tant a la consommation qu'a la production energetique. La question a laquelle la consultation lancee cherchera des reponses est : Comment le Quebec peut-il diminuer sa consommation de petrole et accroitre son independance energetique tout en favorisant le developpement economique et social harmonieux de son territoire?.

  20. Comment analyser la gouvernance territoriale ? Mise à l'épreuve d'une grille de lecture

    OpenAIRE

    Chia, Eduardo; Mathé, Syndhia; Rey-Valette, Hélène; Michel, Laura; Soulard, Christophe-Toussaint; Nougaredes, Brigitte; Jarrige, Françoise; Clement, Camille; Barbe, Eric; Martinand, Pierre; Maurel, Pierre; Guiheneuf, Pierre-Yves

    2010-01-01

    Dans cet article nous présentons une grille d'analyse de la gouvernance territoriale que nous avons construite dans le cadre d'un projet de recherche pluridisciplinaire à partir d'une définition commune de la gouvernance territoriale. La gouvernance territoriale est devenue une question centrale dans le développement territorial et un enjeu pour l'élaboration des politiques publiques. Elaborer une grille d'analyse sur la gouvernance territoriale ne va pas de soi ; nous illustrerons son opérat...

  1. Advances in understanding the molecular basis of the first steps in color vision

    Science.gov (United States)

    Hofmann, Lukas; Palczewski, Krzysztof

    2015-01-01

    Serving as one of our primary environmental inputs, vision is the most sophisticated sensory system in humans. Here, we present recent findings derived from energetics, genetics and physiology that provide a more advanced understanding of color perception in mammals. Energetics of cis–trans isomerization of 11-cis-retinal accounts for color perception in the narrow region of the electromagnetic spectrum and how human eyes can absorb light in the near infrared (IR) range. Structural homology models of visual pigments reveal complex interactions of the protein moieties with the light sensitive chromophore 11-cis-retinal and that certain color blinding mutations impair secondary structural elements of these G protein-coupled receptors (GPCRs). Finally, we identify unsolved critical aspects of color tuning that require future investigation. PMID:26187035

  2. Optoelectronic stereoscopic device for diagnostics, treatment, and developing of binocular vision

    Science.gov (United States)

    Pautova, Larisa; Elkhov, Victor A.; Ovechkis, Yuri N.

    2003-08-01

    Operation of the device is based on alternative generation of pictures for left and right eyes on the monitor screen. Controller gives pulses on LCG so that shutter for left or right eye opens synchronously with pictures. The device provides frequency of switching more than 100 Hz, and that is why the flickering is absent. Thus, a separate demonstration of images to the left eye or to the right one in turn is obtained for patients being unaware and creates the conditions of binocular perception clsoe to natural ones without any additional separation of vision fields. LC-cell transfer characteristic coodination with time parameters of monitor screen has enabled to improve stereo image quality. Complicated problem of computer stereo images with LC-glasses is so called 'ghosts' - noise images that come to blocked eye. We reduced its influence by adapting stereo images to phosphor and LC-cells characteristics. The device is intended for diagnostics and treatment of stabismus, amblyopia and other binocular and stereoscopic vision impairments, for cultivating, training and developing of stereoscopic vision, for measurements of horizontal and vertical phoria, phusion reserves, the stereovision acuity and some else, for fixing central scotoma borders, as well as suppression scotoma in strabismus too.

  3. Les semences d’arachide en milieu paysannal africain : éléments pour une organisation de la filière

    Directory of Open Access Journals (Sweden)

    Schilling Robert

    2001-09-01

    , dans 14 pays de la sous-région, en liaison avec le Projet Germplasm Arachide (GGP, encadré 1 et en prévision d’une poursuite des opérations GGP plus spécialement axée sur l’appui direct à la production semencière. Il convient donc à présent de procéder à une analyse critique des expériences en cours et des données disponibles.

  4. Discourses of Contrast and Deficiency: a Lexicogrammatical Analysis of first Nations Representation in Samuel Hearne’s Journey (1795 Discours de contraste et de manque : analyse lexico-grammaticale d’une représentation des premières nations dans Le voyage de Samuel Hearne (1795

    Directory of Open Access Journals (Sweden)

    Christoph Schubert

    2009-10-01

    Full Text Available Cet article explore la représentation linguistique des indigènes canadiens, en particulier la culture des Chipewyans dans A Journey from Prince of Wales’s Fort in Hudson’s Bay to the Northern Ocean de Samuel Hearne. Le but de cet article est de démontrer que la vision impérialiste de l’auteur peut se lire à partir d’une série d’éléments lexico-grammaticaux correspondants. Nous nous intéressons ici à deux stratégies discursives exprimant la perspective eurocentrée à l’encontre des populations indigènes du Canada.Tout d’abord, Hearne emploie une « rhétorique du contraste » qui renforce le concept de différence culturelle et le mode de vie européen comme culture de référence. Les contrastes se manifestent non seulement dans des groupes lexicaux antonymes, dans plusieurs formes linguistiques de comparaison mais aussi dans des conjonctions et des adverbes adversatifs. De plus, dans les rares cas où la parole est donnée aux indigènes sous la forme de discours rapporté, leurs discours contribuent de façon caractéristique à la dissociation culturelle. Une « rhétorique du manque » accentue l’idée d’une supériorité européenne, en exprimant les carences culturelles des indigènes. Ceci s’accomplit linguistiquement par des quantificateurs de rareté et plusieurs formes de négations qui fonctionnent comme une métaphore (celle d’une pénurie de civilisation. À un niveau métalinguistique, le texte révèle une crise de la représentation descriptive, puisque Hearne considère certains incidents comme « au-delà de la description », postulant que le manque de culture des indigènes est responsable d’une perte du langage.

  5. Agriculture urbaine en Afrique de l'Ouest : Une contribution à la ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Agriculture urbaine en Afrique de l'Ouest : Une contribution à la sécurité alimentaire et à l'assainissement des villes. Couverture du livre Agriculture urbaine en Afrique de l'Ouest : Une contribution à la. Directeur(s):. Olanrewaju B. Smith. Maison(s) d'édition: CTA, CRDI. 1 janvier 1999. ISBN : Épuisé. 240 pages. e-ISBN :.

  6. Regard critique sur une période sans but : Antigone de Valeria Parrella

    Directory of Open Access Journals (Sweden)

    Patrizia Farinelli

    2015-04-01

    Full Text Available Seul un petit nombre de mythes classiques ont retenu autant l'attention que celui d'Antigone. Pendant l'Idéalisme et tout le siècle suivant, l'intérêt pour la version de Sophocle de ce mythe – et plus généralement pour la tragédie classique – s'explique, selon George Steiner, par une conception tragique de la condition humaine (Steiner, 1984, 2. Quelles seraient alors les raisons de cet intérêt à une époque plus récente, sujette à une perte du sens du tragique ? Car, même durant les soixante dernières années, l'histoire de la fille d'Œdipe a été revisitée avec une fréquence surprenante. Selon Hannes Koch (1992, 23, auteur d'une étude sur la réception de la figure d'Antigone dans la littérature allemande du XXe siècle, la mise en valeur de ce personnage est liée à un moment où les droits de l'homme sont ignorés par le pouvoir. Et ce phénomène de mise en valeur implique toujours une crispation dans la sphère politique ayant pour conséquence de souligner justement l'importance politique du geste d'Antigone.

  7. FORMER A L’EXERCICE D’UNE MEDECINE BIOTECHNOLOGIQUE ET HUMAINE

    Directory of Open Access Journals (Sweden)

    Jacques BRINGER

    2017-05-01

    Full Text Available Le bond en avant de la médecine au cours des dernières décennies s’est appuyé sur la recherche, l’innovation dans les nouvelles biotechnologies permettant le développement de soins plus efficaces, moins invasifs, mieux ciblés pour nombre de maladies. Dans le même temps, une meilleure gestion des risques et une organisation plus centrée sur le patient impliquent une étroite coopération entre les professionnels de santé activés selon les besoins du patient. Les étudiants en médecine doivent être entrainés à acquérir la pratique des nouvelles technologies et à se préparer à l’action en équipe avant d’intervenir dans le soin. Un tel entrainement par simulation vise à développer des mises en situation de « vraie vie » incluant l’obtention de compétences individuelles ou collectives et l’aptitude des cliniciens à une décision partagée et aux relations humaines telles que la capacité d’écoute, d’annonce et d’accompagnement s’appuyant sur le questionnement éthique et le souci de la personne.

  8. Vers une éthique climatique plus efficace : motivations et incitations

    Directory of Open Access Journals (Sweden)

    Michel Bourban

    2014-06-01

    Full Text Available Cet article vise à justifier, puis à appliquer une éthique climatique centrée sur les intérêts des acteurs économiques. Après avoir expliqué pourquoi le changement climatique pose un problème important de motivation, je montre pour quelles raisons les incitations peuvent au moins partiellement y remédier. Je développe ensuite deux possibilités d’institutionnalisation de l’éthique des incitations. La première consiste en une taxe internationale augmentant progressivement le coût des émissions de dioxyde de carbone, un dispositif auquel il convient d’ajouter des subsides pour la recherche, le développement et le déploiement des énergies renouvelables. La seconde consiste en un marché global du carbone qui vise également à décourager l’utilisation des combustibles fossiles et à encourager l’utilisation de sources alternatives d’énergie. L’objectif est de montrer qu’une éthique climatique prenant en compte le problème de la motivation est plus efficace qu’une position qui se limite aux devoirs moraux incombant aux consommateurs et producteurs, soit de réduire leurs émissions.

  9. Visual Motion Perception and Visual Attentive Processes.

    Science.gov (United States)

    1988-04-01

    88-0551 Visual Motion Perception and Visual Attentive Processes George Spering , New YorkUnivesity A -cesson For DTIC TAB rant AFOSR 85-0364... Spering . HIPSt: A Unix-based image processing syslem. Computer Vision, Graphics, and Image Processing, 1984,25. 331-347. ’HIPS is the Human Information...Processing Laboratory’s Image Processing System. 1985 van Santen, Jan P. It, and George Spering . Elaborated Reichardt detectors. Journal of the Optical

  10. Comment les travaux de recherche subventionnés par le CRDI ont ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    25 oct. 2010 ... Une vision planétaire pour les petites entreprises d'Égypte. Autrefois ignorées et sous-évaluées, les petites entreprises sont aujourd'hui à l'avant-plan des préoccupations alors que l'Égypte prend des mesure. Voir davantageUne vision planétaire pour les petites entreprises d'Égypte ...

  11. Le kyste hydatique rénal primitif: Une première observation mauritanienne

    Directory of Open Access Journals (Sweden)

    T.I. Boudhaye

    2016-12-01

    Full Text Available L’hydatidose est une affection parasitaire rare qui sévit à l’état endémique dans certains pays du bassin méditerranéen. La localisation rénale est rare et n’existe que dans 2 à 3% des formes viscérales. En Mauritanie, cette pathologie est extrêmement rare, nous rapportons une première observation d’une localisation rénale de l’hydatidose dans cette région ouest africaine.

  12. The CCH Vision Stimulation Program for Infants with Low Vision: Preliminary Results.

    Science.gov (United States)

    Leguire, L. E.; And Others

    1992-01-01

    This study evaluated the Columbus (Ohio) Children's Hospital vision stimulation program, involving in-home intervention with 15 visually impaired infants. Comparison with controls indicated benefits of appropriate vision stimulation in increasing the neural foundation for vision and visual-motor function in visually impaired infants. (Author/DB)

  13. Les effets potentiels du taping chez une population adulte souffrant d'un conflit sous-acromial

    OpenAIRE

    Roch, Sylvie; Thétaz, Alain; Balthazard, Pierre

    2012-01-01

    Introduction : Le conflit sous-acromial est une pathologie fréquente qui touche une grande partie de la population. Quelques revues de la littérature recommandent une prise en charge spécifique, mais peu d’études proposent le taping comme adjuvant aux traitements préconisés. Ainsi ce travail de bachelor a pour objectif de déterminer les effets potentiels du taping chez une population adulte souffrant de conflit sous-acromial. Méthodologie : Notre recherche d’études s’est effectuée de janvier ...

  14. Le Syndrome de Denys-Drash, une Cause Rare de Syndrome ...

    African Journals Online (AJOL)

    Le syndrome de Denys-Drash (DD) est une affection génétique rare due à la mutation du gène WT1, impliqué dans la morphogenèse des organes génitaux externes et du rein. Il associe un syndrome néphrotique congénital et une ambiguïté sexuelle. Les premiers signes surviennent dès les 3 premiers mois de vie sous ...

  15. Michel Houellebecq : un homme, une (soumission

    Directory of Open Access Journals (Sweden)

    Marc Smeets

    2015-12-01

    Full Text Available Michel Houellebecq, l’auteur le plus controversé de la littérature française contemporaine, semble s’astreindre à une seule et unique mission : celle d’être « vrai » à n’importe quel prix. Observateur et peintre de la société actuelle dans tous ses états, l’auteur de Soumission s’inscrit dans une tradition littéraire qui remonte au XIXe siècle, prolongeant ainsi les fictions de Balzac, de Zola et de Huysmans. De ses prédécesseurs Houellebecq hérite d’un certain goût pour la controverse, talent qui fait naturellement la pluie et le beau temps dans la presse. Le rôle que jouent la documentation et la figure du célibataire permet de situer l’écrivain dans le sillage de la tradition réalistico-naturaliste.

  16. Machine Vision Handbook

    CERN Document Server

    2012-01-01

    The automation of visual inspection is becoming more and more important in modern industry as a consistent, reliable means of judging the quality of raw materials and manufactured goods . The Machine Vision Handbook  equips the reader with the practical details required to engineer integrated mechanical-optical-electronic-software systems. Machine vision is first set in the context of basic information on light, natural vision, colour sensing and optics. The physical apparatus required for mechanized image capture – lenses, cameras, scanners and light sources – are discussed followed by detailed treatment of various image-processing methods including an introduction to the QT image processing system. QT is unique to this book, and provides an example of a practical machine vision system along with extensive libraries of useful commands, functions and images which can be implemented by the reader. The main text of the book is completed by studies of a wide variety of applications of machine vision in insp...

  17. Color vision abnormality as an initial presentation of the complete type of congenital stationary night blindness.

    Science.gov (United States)

    Tan, Xue; Aoki, Aya; Yanagi, Yasuo

    2013-01-01

    Patients with the complete form of congenital stationary night blindness (CSNB) often have reduced visual acuity, myopia, impaired night vision, and sometimes nystagmus and strabismus, however, they seldom complain of color vision abnormality. A 17-year-old male who was at technical school showed abnormalities in the color perception test for employment, and was referred to our hospital for a detailed examination. He had no family history of color vision deficiency and no other symptoms. During the initial examination, his best-corrected visual acuity was 1.2 in both eyes. His fundus showed no abnormalities except for somewhat yellowish reflex in the fovea of both eyes. Electroretinogram (ERG) showed a good response in cone ERG and 30 Hz flicker ERG, however, the bright flash, mixed rod and cone ERG showed a negative type with a reduced b-wave (positive deflection). There was no response in the rod ERG, either. From the findings of the typical ERG, the patient was diagnosed with complete congenital stationary night blindness. This case underscores the importance of ERG in order to diagnose the cause of a color vision anomaly.

  18. Agnosic vision is like peripheral vision, which is limited by crowding.

    Science.gov (United States)

    Strappini, Francesca; Pelli, Denis G; Di Pace, Enrico; Martelli, Marialuisa

    2017-04-01

    Visual agnosia is a neuropsychological impairment of visual object recognition despite near-normal acuity and visual fields. A century of research has provided only a rudimentary account of the functional damage underlying this deficit. We find that the object-recognition ability of agnosic patients viewing an object directly is like that of normally-sighted observers viewing it indirectly, with peripheral vision. Thus, agnosic vision is like peripheral vision. We obtained 14 visual-object-recognition tests that are commonly used for diagnosis of visual agnosia. Our "standard" normal observer took these tests at various eccentricities in his periphery. Analyzing the published data of 32 apperceptive agnosia patients and a group of 14 posterior cortical atrophy (PCA) patients on these tests, we find that each patient's pattern of object recognition deficits is well characterized by one number, the equivalent eccentricity at which our standard observer's peripheral vision is like the central vision of the agnosic patient. In other words, each agnosic patient's equivalent eccentricity is conserved across tests. Across patients, equivalent eccentricity ranges from 4 to 40 deg, which rates severity of the visual deficit. In normal peripheral vision, the required size to perceive a simple image (e.g., an isolated letter) is limited by acuity, and that for a complex image (e.g., a face or a word) is limited by crowding. In crowding, adjacent simple objects appear unrecognizably jumbled unless their spacing exceeds the crowding distance, which grows linearly with eccentricity. Besides conservation of equivalent eccentricity across object-recognition tests, we also find conservation, from eccentricity to agnosia, of the relative susceptibility of recognition of ten visual tests. These findings show that agnosic vision is like eccentric vision. Whence crowding? Peripheral vision, strabismic amblyopia, and possibly apperceptive agnosia are all limited by crowding, making it

  19. Eye movements and attention in reading, scene perception, and visual search.

    Science.gov (United States)

    Rayner, Keith

    2009-08-01

    Eye movements are now widely used to investigate cognitive processes during reading, scene perception, and visual search. In this article, research on the following topics is reviewed with respect to reading: (a) the perceptual span (or span of effective vision), (b) preview benefit, (c) eye movement control, and (d) models of eye movements. Related issues with respect to eye movements during scene perception and visual search are also reviewed. It is argued that research on eye movements during reading has been somewhat advanced over research on eye movements in scene perception and visual search and that some of the paradigms developed to study reading should be more widely adopted in the study of scene perception and visual search. Research dealing with "real-world" tasks and research utilizing the visual-world paradigm are also briefly discussed.

  20. Memory for Random Time Patterns in Audition, Touch, and Vision.

    Science.gov (United States)

    Kang, HiJee; Lancelin, Denis; Pressnitzer, Daniel

    2018-03-22

    Perception deals with temporal sequences of events, like series of phonemes for audition, dynamic changes in pressure for touch textures, or moving objects for vision. Memory processes are thus needed to make sense of the temporal patterning of sensory information. Recently, we have shown that auditory temporal patterns could be learned rapidly and incidentally with repeated exposure [Kang et al., 2017]. Here, we tested whether rapid incidental learning of temporal patterns was specific to audition, or if it was a more general property of sensory systems. We used a same behavioral task in three modalities: audition, touch, and vision, for stimuli having identical temporal statistics. Participants were presented with sequences of acoustic pulses for audition, motion pulses to the fingertips for touch, or light pulses for vision. Pulses were randomly and irregularly spaced, with all inter-pulse intervals in the sub-second range and all constrained to be longer than the temporal acuity in any modality. This led to pulse sequences with an average inter-pulse interval of 166 ms, a minimum inter-pulse interval of 60 ms, and a total duration of 1.2 s. Results showed that, if a random temporal pattern re-occurred at random times during an experimental block, it was rapidly learned, whatever the sensory modality. Moreover, patterns first learned in the auditory modality displayed transfer of learning to either touch or vision. This suggests that sensory systems may be exquisitely tuned to incidentally learn re-occurring temporal patterns, with possible cross-talk between the senses. Copyright © 2018 IBRO. Published by Elsevier Ltd. All rights reserved.

  1. Learning Visual Representations for Perception-Action Systems

    DEFF Research Database (Denmark)

    Piater, Justus; Jodogne, Sebastien; Detry, Renaud

    2011-01-01

    and RLJC, our second method learns structural object models for robust object detection and pose estimation by probabilistic inference. To these models, the method associates grasp experiences autonomously learned by trial and error. These experiences form a nonparametric representation of grasp success......We discuss vision as a sensory modality for systems that effect actions in response to perceptions. While the internal representations informed by vision may be arbitrarily complex, we argue that in many cases it is advantageous to link them rather directly to action via learned mappings....... These arguments are illustrated by two examples of our own work. First, our RLVC algorithm performs reinforcement learning directly on the visual input space. To make this very large space manageable, RLVC interleaves the reinforcement learner with a supervised classification algorithm that seeks to split...

  2. Vision restoration after brain and retina damage: the "residual vision activation theory".

    Science.gov (United States)

    Sabel, Bernhard A; Henrich-Noack, Petra; Fedorov, Anton; Gall, Carolin

    2011-01-01

    Vision loss after retinal or cerebral visual injury (CVI) was long considered to be irreversible. However, there is considerable potential for vision restoration and recovery even in adulthood. Here, we propose the "residual vision activation theory" of how visual functions can be reactivated and restored. CVI is usually not complete, but some structures are typically spared by the damage. They include (i) areas of partial damage at the visual field border, (ii) "islands" of surviving tissue inside the blind field, (iii) extrastriate pathways unaffected by the damage, and (iv) downstream, higher-level neuronal networks. However, residual structures have a triple handicap to be fully functional: (i) fewer neurons, (ii) lack of sufficient attentional resources because of the dominant intact hemisphere caused by excitation/inhibition dysbalance, and (iii) disturbance in their temporal processing. Because of this resulting activation loss, residual structures are unable to contribute much to everyday vision, and their "non-use" further impairs synaptic strength. However, residual structures can be reactivated by engaging them in repetitive stimulation by different means: (i) visual experience, (ii) visual training, or (iii) noninvasive electrical brain current stimulation. These methods lead to strengthening of synaptic transmission and synchronization of partially damaged structures (within-systems plasticity) and downstream neuronal networks (network plasticity). Just as in normal perceptual learning, synaptic plasticity can improve vision and lead to vision restoration. This can be induced at any time after the lesion, at all ages and in all types of visual field impairments after retinal or brain damage (stroke, neurotrauma, glaucoma, amblyopia, age-related macular degeneration). If and to what extent vision restoration can be achieved is a function of the amount of residual tissue and its activation state. However, sustained improvements require repetitive

  3. Filtering and polychromatic vision in mantis shrimps: themes in visible and ultraviolet vision.

    Science.gov (United States)

    Cronin, Thomas W; Bok, Michael J; Marshall, N Justin; Caldwell, Roy L

    2014-01-01

    Stomatopod crustaceans have the most complex and diverse assortment of retinal photoreceptors of any animals, with 16 functional classes. The receptor classes are subdivided into sets responsible for ultraviolet vision, spatial vision, colour vision and polarization vision. Many of these receptor classes are spectrally tuned by filtering pigments located in photoreceptors or overlying optical elements. At visible wavelengths, carotenoproteins or similar substances are packed into vesicles used either as serial, intrarhabdomal filters or lateral filters. A single retina may contain a diversity of these filtering pigments paired with specific photoreceptors, and the pigments used vary between and within species both taxonomically and ecologically. Ultraviolet-filtering pigments in the crystalline cones serve to tune ultraviolet vision in these animals as well, and some ultraviolet receptors themselves act as birefringent filters to enable circular polarization vision. Stomatopods have reached an evolutionary extreme in their use of filter mechanisms to tune photoreception to habitat and behaviour, allowing them to extend the spectral range of their vision both deeper into the ultraviolet and further into the red.

  4. Micro Vision

    OpenAIRE

    Ohba, Kohtaro; Ohara, Kenichi

    2007-01-01

    In the field of the micro vision, there are few researches compared with macro environment. However, applying to the study result for macro computer vision technique, you can measure and observe the micro environment. Moreover, based on the effects of micro environment, it is possible to discovery the new theories and new techniques.

  5. The Handbook of Medical Image Perception and Techniques

    Science.gov (United States)

    Samei, Ehsan; Krupinski, Elizabeth

    2014-07-01

    1. Medical image perception Ehsan Samei and Elizabeth Krupinski; Part I. Historical Reflections and Theoretical Foundations: 2. A short history of image perception in medical radiology Harold Kundel and Calvin Nodine; 3. Spatial vision research without noise Arthur Burgess; 4. Signal detection theory, a brief history Arthur Burgess; 5. Signal detection in radiology Arthur Burgess; 6. Lessons from dinners with the giants of modern image science Robert Wagner; Part II. Science of Image Perception: 7. Perceptual factors in reading medical images Elizabeth Krupinski; 8. Cognitive factors in reading medical images David Manning; 9. Satisfaction of search in traditional radiographic imaging Kevin Berbaum, Edmund Franken, Robert Caldwell and Kevin Schartz; 10. The role of expertise in radiologic image interpretation Calvin Nodine and Claudia Mello-Thoms; 11. A primer of image quality and its perceptual relevance Robert Saunders and Ehsan Samei; 12. Beyond the limitations of human vision Maria Petrou; Part III. Perception Metrology: 13. Logistical issues in designing perception experiments Ehsan Samei and Xiang Li; 14. ROC analysis: basic concepts and practical applications Georgia Tourassi; 15. Multi-reader ROC Steve Hillis; 16. Recent developments in FROC methodology Dev Chakraborty; 17. Observer models as a surrogate to perception experiments Craig Abbey and Miguel Eckstein; 18. Implementation of observer models Matthew Kupinski; Part IV. Decision Support and Computer Aided Detection: 19. CAD: an image perception perspective Maryellen Giger and Weijie Chen; 20. Common designs of CAD studies Yulei Jiang; 21. Perceptual effect of CAD in reading chest images Matthew Freedman and Teresa Osicka; 22. Perceptual issues in mammography and CAD Michael Ulissey; 23. How perceptual factors affect the use and accuracy of CAD for interpretation of CT images Ronald Summers; 24. CAD: risks and benefits for radiologists' decisions Eugenio Alberdi, Andrey Povyakalo, Lorenzo Strigini and

  6. LA FINANCE ISLAMIQUE A LA FRANÇAISE : UN MOTEUR POUR L’ECONOMIE, UNE ALTERNATIVE ETHIQUE

    OpenAIRE

    BELABES, Abderrazak

    2011-01-01

    L’ouvrage a été réalisé sous la direction de Jean-Paul Laramée, directeur général de Secure Finance, co-organisateur du Forum Français sur la Finance Islamique, fondateur du site Finance Islamique France et de l’Institut Français de la Finance Islamique. Il s’inscrit "dans une perspective pluridisciplinaire et internationale" (p. 7) et comprend respectivement une note de l’éditeur (pp. 7-11), une première préface d’Ahmad Jachi, premier gouverneur de la Banque du Liban (p. 13), une seconde d’H...

  7. Qui sera le nouvel Einstein ? Vers une nouvelle theorie de la gravitation

    Science.gov (United States)

    Bonnet-Bidaud, J. M.

    1999-10-01

    Un debat de plus d'un siecle a resurgi ces toutes dernieres annees avec une vigueur nouvelle. L'enjeu ? Mettre fin, ni plus ni moins, a l'une des contradictions les plus inouies de la physique fondamentale, en reconciliant mecanique quantique et relativite generale. En effet, a l'heure ou la gravitation semble enfin sur le point de fusionner avec les trois autres forces de la nature. il est certain que la relativite d'Einstein doit etre bientot remplacer par une autre theorie... Reste quye tous les physiciens sont loin de s'accorder sur la marche a suivree. Gravitation quantique, relativite d'echelle, supersymetrie, les candidates ne manquent pas.

  8. Determination of distances to visible points of bodies in a system of visual perception

    Energy Technology Data Exchange (ETDEWEB)

    Nevskiy, I V; Osadchiy, S M; Solntsev, S V

    1981-09-01

    An examination is made of problems connected with the determination of the form of bodies in a system of visual perception. The effect of parallax, which is familiar from the psychology of vision, is basic for the construction of a model of a system of visual perception. An estimate of the error of discrete realization of the relationships obtained in solution of the problems is also made. A model experiment is described. 12 references.

  9. Le camfranglais, né de l’acclimatement/acclimatation du français, au cœur d’une glottonomie socio-profane

    Directory of Open Access Journals (Sweden)

    Venant Eloundou Eloundou

    2016-01-01

    Full Text Available Cette contribution analyse les perceptions que les internautes des sites Forum Bonaberi.com et Cameroon-Info.Net ont du camfranglais, né du processus d’acclimatement/acclimatation du français au Cameroun. Mettant à contribution les discours des camfranglophones, l’approche glottonomique et l’imaginaire linguistique, l’étude se focalise sur les représentations systémiques et sociolinguistiques du camfranglais. S’agissant du premier axe, l’analyse des interventions discursives révèle les spécificités linguistiques du camfranglais, en l’opposant au pidgin-english-camerounais né de l’anglais et aux variétés de français parlé au Cameroun. Le second axe examine l’imaginaire de la variation sociolangagière du camfrançais. Il en découle que les internautes ont une saisie variationniste de cet parler selon trois niveaux : diachronique, diatopique et diaphasique. Ce camfranglais apparaît dans les discours épilinguistiques analysés comme une langue à part entière : d’où la revendication de ses statuts et ses fonctions officiels ; voire sa prise en compte glottopolitique. Toutes ces représentations faites par ce qu’on peut appeler les acteurs glottonomiques profanes permettent d’aboutir à la conclusion selon laquelle la gestion des problématiques glottopolitiques doit tenir compte de toutes les composantes sociales, pour un développement durable, stimulé par des langues. Par ailleurs, relativement à la linguistique française, cette analyse permet de saisir les tensions sociolinguistiques et les modalités de représentations impliquant le français et le camfranglais. Si le français constitue une langue matrice pour le camfranglais, il ressort de cette réflexion que ses locuteurs construisent des représentations visant à établir une frontière linguistique et sociolinguistique entre la langue mère (français et le camfranglais dérivé.

  10. D'une industrie... l'autre?

    NARCIS (Netherlands)

    Musso, S.; Nguyen, V.K.

    2013-01-01

    À partir d’une contextualisation du texte de Cindy Patton, les auteur-e-s invitent à penser l’actualité des questions évoquées à l’aune d’enjeux contemporains relatifs à la production d’identités et de communautés que donnent à voir l’établissement des « cibles » de la prévention et du traitement du

  11. Une introduction à MATLAB c

    OpenAIRE

    CREMONA, Christian; LABORATOIRE CENTRAL DES PONTS ET CHAUSSEES - LCPC

    2002-01-01

    MATLAB c présente toutes les fonctionnalités des approches récentes de la programmation : programmation objet basée sur des hiérarchies de classes, programmation événementielle du graphisme. MATLAB c présente une aide en ligne très complète sous format html des différentes fontions accessibles. COMPTE RENDU DE RECHERCHE

  12. Research on robot navigation vision sensor based on grating projection stereo vision

    Science.gov (United States)

    Zhang, Xiaoling; Luo, Yinsheng; Lin, Yuchi; Zhu, Lei

    2016-10-01

    A novel visual navigation method based on grating projection stereo vision for mobile robot in dark environment is proposed. This method is combining with grating projection profilometry of plane structured light and stereo vision technology. It can be employed to realize obstacle detection, SLAM (Simultaneous Localization and Mapping) and vision odometry for mobile robot navigation in dark environment without the image match in stereo vision technology and without phase unwrapping in the grating projection profilometry. First, we research the new vision sensor theoretical, and build geometric and mathematical model of the grating projection stereo vision system. Second, the computational method of 3D coordinates of space obstacle in the robot's visual field is studied, and then the obstacles in the field is located accurately. The result of simulation experiment and analysis shows that this research is useful to break the current autonomous navigation problem of mobile robot in dark environment, and to provide the theoretical basis and exploration direction for further study on navigation of space exploring robot in the dark and without GPS environment.

  13. Color vision abnormality as an initial presentation of the complete type of congenital stationary night blindness

    Directory of Open Access Journals (Sweden)

    Tan X

    2013-08-01

    Full Text Available Xue Tan, Aya Aoki, Yasuo YanagiDepartment of Ophthalmology, University of Tokyo School of Medicine, Hongo, Bunkyo-ku, Tokyo, JapanAbstract: Patients with the complete form of congenital stationary night blindness (CSNB often have reduced visual acuity, myopia, impaired night vision, and sometimes nystagmus and strabismus, however, they seldom complain of color vision abnormality. A 17-year-old male who was at technical school showed abnormalities in the color perception test for employment, and was referred to our hospital for a detailed examination. He had no family history of color vision deficiency and no other symptoms. During the initial examination, his best-corrected visual acuity was 1.2 in both eyes. His fundus showed no abnormalities except for somewhat yellowish reflex in the fovea of both eyes. Electroretinogram (ERG showed a good response in cone ERG and 30 Hz flicker ERG, however, the bright flash, mixed rod and cone ERG showed a negative type with a reduced b-wave (positive deflection. There was no response in the rod ERG, either. From the findings of the typical ERG, the patient was diagnosed with complete congenital stationary night blindness. This case underscores the importance of ERG in order to diagnose the cause of a color vision anomaly.Keywords: congenital stationary night blindness, CSNB, electroretinogram, ERG, color vision defect

  14. Jeux de rôles pour enfants : une nouvelle forme de fiction ludique

    Directory of Open Access Journals (Sweden)

    Sébastien Kapp

    2011-12-01

    Full Text Available Comment ethnographier la place de la création fictionnelle chez l’enfant ? Nous proposons ici une étude de cas d’une pratique à la croisée du jeu de rôle enfantin spontané et du jeu de rôle grandeur nature pour adulte. Menée sous la forme d’un stage estival, cette activité nous permet de comprendre comment adultes et enfants peuvent ponctuellement participer ensemble à l’écriture d’un récit qui prendra la forme d’un jeu en actes et en paroles. Une des caractéristiques principales de cette forme hybride est que l’enfant est placé dans une position d’auteur, d’acteur et de spectateur. Mais contrairement à ses propres jeux, il est en permanence sous la surveillance et la conduite d’adultes qui supervisent le développement du récit et la conformité des actions par rapport aux règles. Le jeune joueur est donc dans une posture originale : il produit une partie du contenu narratif du jeu dont il n’est pas l’acteur unique (en créant par exemple son personnage. Lui aussi veut raconter une histoire, mettre en place un scénario, créer des règles et faire jouer les adultes, comme dans son jeu enfantin. Mais les règles changent, il n’est plus omnipotent et doit jouer dans des cadres de simulation qu’il contribue à définir.

  15. UNE CULTURE MEDITERRANEENNE FRAGMENTEE : LA REVENDICATION AMAZIGHE ENTRE LOCAL(ITE) ET TRANSNATIONAL(ITE)

    OpenAIRE

    Pouessel, Stéphanie

    2010-01-01

    Ce texte se propose d'offrir une perspective transfrontalière des mouvements culturels berbères au Maghreb et en France. L'objectif est de retracer les cheminements de la berbérité qui peuvent dans le même temps construire une revendication spécifique et locale et se brancher à une lutte berbère dans son acception globale. Il s'agit tout d'abord de retracer les contextes politiques, culturels et sociaux qui enserrent les revendications dans chaque pays (principalement Maroc, Algérie, France m...

  16. Vers une typologie des modes de contrôle de gestion fondée sur la communication

    OpenAIRE

    Chtioui , Tawhid

    2008-01-01

    International audience; En se fondant sur la mesure comme fil directeur méthodologique, cette recherche montre l'interet d'une approche communicationnelle pour une meilleure compréhension du processus de contrôle de gestion. Pour ce faire, nous avons conduit une démarche de recherche en trois étapes : Une première phase empirique exploratoire a été menée, à travers un processus Delphi, auprès de 20 responsables de contrôle de gestion de 20 grandes entreprises françaises. Une deuxième phase em...

  17. La recherche écosanté en pratique : Applications novatrices d'une ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    22 juil. 2014 ... ... de l'écosanté forment un tout qui prouve à quel point il s'agit d'un domaine dynamique et en évolution constante doté d'une mission claire et animé par une communauté de praticiens scientifique toujours plus large. Mario Henry Rodríguez, Directeur général, Instituto Nacional de Salud Pública, Mexique.

  18. Une recension des écrits concernant la réalité psychoaffective des femmes ayant une vulvodynie : Difficultés rencontrées et stratégies développées

    Science.gov (United States)

    Cantin-Drouin, Maude; Damant, Dominique; Turcotte, Daniel

    2008-01-01

    HISTORIQUE : Au cours des trois dernières décennies, une attention grandissante a été portée à l’étude du syndrome de vulvodynie, soit un inconfort vulvaire chronique inexpliqué, éprouvé en l’absence de pathologie précisée. En plus d’avoir des répercussions physiques, l’expérience de la vulvodynie comporte une dimension psychosociale. OBJECTIF : Cet article vise à faire une recension des écrits sur la réalité psychoaffective des femmes qui éprouvent une vulvodynie. MÉTHODE : Une recherche documentaire basée sur une exploration systématique de textes présentant des résultats de recherche et recensés dans les principales banques de données en sciences sociales, dont Dissertation Abstracts, Current Contents et PsycINFO, a été réalisée. RÉSULTATS : Cette recension des écrits révèle, malgré la présence de certains résultats divergents, que les femmes ayant une vulvodynie affrontent souvent des difficultés identitaires et psychologiques, qui sont influencées notamment par les normes sociales de sexualité et de féminité. Pour composer avec ces difficultés, les femmes développent différentes stratégies visant à diminuer le stress occasionné par la douleur et à améliorer leur bien-être psychologique. CONCLUSION : Les difficultés relationnelles et psychologiques vécues par les femmes ayant une vulvodynie ne découlent pas seulement de la douleur physique, mais aussi du sens qu’elles lui accordent, souvent influencé par les discours sociaux sur l’hétérosexualité et la féminité. Il importe donc d’intervenir auprès des femmes en tenant compte de l’influence du contexte social tout en poursuivant le développement des connaissances sur les aspects psychosociaux de cette expérience. PMID:18592063

  19. Chemicals Industry Vision

    Energy Technology Data Exchange (ETDEWEB)

    none,

    1996-12-01

    Chemical industry leaders articulated a long-term vision for the industry, its markets, and its technology in the groundbreaking 1996 document Technology Vision 2020 - The U.S. Chemical Industry. (PDF 310 KB).

  20. Low Vision Tips

    Science.gov (United States)

    ... this page: https://medlineplus.gov/lowvision.html MedlinePlus: Low Vision Tips We are sorry. MedlinePlus no longer maintains the For Low Vision Users page. You will still find health resources ...

  1. Development of Moire machine vision

    Science.gov (United States)

    Harding, Kevin G.

    1987-10-01

    Three dimensional perception is essential to the development of versatile robotics systems in order to handle complex manufacturing tasks in future factories and in providing high accuracy measurements needed in flexible manufacturing and quality control. A program is described which will develop the potential of Moire techniques to provide this capability in vision systems and automated measurements, and demonstrate artificial intelligence (AI) techniques to take advantage of the strengths of Moire sensing. Moire techniques provide a means of optically manipulating the complex visual data in a three dimensional scene into a form which can be easily and quickly analyzed by computers. This type of optical data manipulation provides high productivity through integrated automation, producing a high quality product while reducing computer and mechanical manipulation requirements and thereby the cost and time of production. This nondestructive evaluation is developed to be able to make full field range measurement and three dimensional scene analysis.

  2. Prevalence de la cataracte senile dans une population rurale du ...

    African Journals Online (AJOL)

    But: Evaluer la prévalence de la cataracte sénile dans le canton de Kévé, préfecture de l'Avé au Togo. Méthodologie: Il s'agit d'une étude transversale dans trois villages et le centre ville de Kévé. Les patients étaient regroupés et examinés à la lumière du jour à l'aide d'une lampe torche et un ophtalmoscope direct à piles ...

  3. Cancer du rein et Grossesse: A propos d’une nouvelle observation

    Directory of Open Access Journals (Sweden)

    A. Majdoub

    2017-12-01

    Nous rapportons le cas d’une patiente âgée de 38 ans, sans antécédents pathologiques notables, enceinte avec un terme de 16 semaines d’aménorrhée, présentant des lombalgies gauches. Le diagnostic de tumeur rénale était retenu sur les données du couple échographie rénale et IRM abdominale. La patiente a bénéficié d’une néphrectomie élargie par voie lombaire. L’analyse histologique de la pièce de néphrectomie totale a révélé un adénocarcinome à cellules claires. L’évolution était favorable après le traitement avec une grossesse menée à terme.

  4. The Perception-Action Model

    DEFF Research Database (Denmark)

    Grünbaum, Thor

    2017-01-01

    Milner and Goodale’s Two Visual Systems Hypothesis (TVSH) is regarded as common ground in recent discussions of visual consciousness. A central part of TVSH is a functional model of vision and action (a functional perception-action model, PAM for short). In this paper, I provide a brief overview...... of these current discussions and argue that PAM is ambiguous between a strong and a weak version. I argue that, given a standard way of individuating computational mechanisms, the available evidence cannot be used to distinguish between these versions. This not only has consequences for philosophical theories...

  5. Review: Familiarity to Vision Rehabilitation Process

    Directory of Open Access Journals (Sweden)

    Nasser Sadegh-Pour

    2006-10-01

    Full Text Available Considering the numbers of low vision patients who have been visited and treated in eye clinics, sometimes there is no exact treatment to increase their visual acuity. Therefore, the necessity to pay attention to vision rehabilitation for them is strongly felt. The aims of this essay are to define vision rehabilitation and its process in relevant centers (called Low Vision Clinic.The statistic of low vision people is reported and the method of collecting data is described. Standard definition, causes of low vision and related diseases (congenital, heredity, acquired… are explained. In addition, low vision aids and role of test and prescription are discussed. Sometimes ophthalmologists and optometrists can not exactly cure patient to raise their V.A because there is no treatment or drug or ordinary glasses. In these cases the clients should refer to low vision clinic and visit low vision specialist on vision rehabilitation process. After primary evaluation they are tested completely and at the end are prescribed proper low vision aid and also provided with advice in relation to career, education role and training techniques especially in children. At the last part of present dissertation, some examples are provided to show effectiveness of vision rehabilitation and low vision aid among the clients in different countries.

  6. Head-Mounted Display Technology for Low Vision Rehabilitation and Vision Enhancement

    Science.gov (United States)

    Ehrlich, Joshua R.; Ojeda, Lauro V.; Wicker, Donna; Day, Sherry; Howson, Ashley; Lakshminarayanan, Vasudevan; Moroi, Sayoko E.

    2017-01-01

    Purpose To describe the various types of head-mounted display technology, their optical and human factors considerations, and their potential for use in low vision rehabilitation and vision enhancement. Design Expert perspective. Methods An overview of head-mounted display technology by an interdisciplinary team of experts drawing on key literature in the field. Results Head-mounted display technologies can be classified based on their display type and optical design. See-through displays such as retinal projection devices have the greatest potential for use as low vision aids. Devices vary by their relationship to the user’s eyes, field of view, illumination, resolution, color, stereopsis, effect on head motion and user interface. These optical and human factors considerations are important when selecting head-mounted displays for specific applications and patient groups. Conclusions Head-mounted display technologies may offer advantages over conventional low vision aids. Future research should compare head-mounted displays to commonly prescribed low vision aids in order to compare their effectiveness in addressing the impairments and rehabilitation goals of diverse patient populations. PMID:28048975

  7. Maladie de Horton révélée par une dyspnée | Mahfoudhi | Pan ...

    African Journals Online (AJOL)

    Les manifestations pleuro-pulmonaires de la maladie de Horton sont rares et peu connues. Elles peuvent être inaugurales, à l'origine d'un retard à la prise en charge si elles sont méconnues. Il s'agissait d'un patient âgé de 75 ans, admis pour une dyspnée, une toux chronique et une fièvre. Il a reçu une antibiothérapie et a ...

  8. Une poétique du vœu : inspiration poétique et mystique impériale dans le poème XIX (et quelques autres d’Optatianus Porfyrius

    Directory of Open Access Journals (Sweden)

    Marie-Odile Bruhat

    2010-11-01

    Full Text Available La majorité des poèmes d’Optatianus Porfyrius qui nous sont parvenus est dédiée à l’empereur Constantin et consacrée à son éloge. Mais dans cette poésie visuelle d’un nouveau genre, la célébration de l’art poétique tient une place aussi importante que la célébration impériale. Comment considérer le discours proprement poétique d’Optatianus ? Est-il simplement juxtaposé au discours politique ? Relève-t-il d’une pure convention ornementale ? Ces questions sont d’autant plus pertinentes que, loin de présenter le procédé visuel dont il est l’inventeur comme un art technicien, Optatianus revendique le double titre de poiètès et de uates et convoque les divinités de l’inspiration, Phébus et les Muses, alors même que ses poèmes se font l’écho de la nouvelle théologie chrétienne du pouvoir. La réponse apparaît double. D’une part, la poésie d’Optatianus peut être définie comme votive. Ses poèmes s’inscrivent dans la liturgie du pouvoir, c’est-à-dire dans le cadre d’une théologie impériale qui repose sur l’affirmation de l’éternité de la victoire et sur le renouvellement du charisme victorieux à travers le rituel des voeux. Par son discours sur Phébus et les Muses, Optatianus met en place une véritable poétique du voeu, qui consiste à couler la mystique de l’inspiration dans le moule de la mystique impériale. D’autre part, ce projet poétique répond à bien des égards à l’attente impériale. Il rencontre la volonté de Constantin de développer une politique culturelle, et se plie à quelques traits caractéristiques de sa religiosité : conviction de la nécessité du secours divin dans les actions humaines, d’une inspiration divine dont Constantin a fait lui-même l’expérience, attention aux signes et aux visions, attachement à un charisme solaire qui coexiste sous une forme « neutralisée » avec sa foi chrétienne. Le poème XIX, composé à l

  9. Le scoutisme: une éducation au service des droits de l'enfant

    OpenAIRE

    Namani, Lirija; Darbellay, Frédéric

    2016-01-01

    Le scoutisme est apparu, en 1907, à une époque caractérisée par l’industrialisation et des problématiques propres à celle-ci ; à une époque où l’enfant n’avait aucun droit, mais qui néanmoins était présent et actif au sein de la société. Il était tantôt travailleur, écolier, propriété du père et discriminé. Son statut a toutefois évolué vers une meilleure reconnaissance. Celle-ci résulte des changements sociaux, politiques, économiques et juridiques apparus au sein de la société. À l’origine,...

  10. Genre et mutualisation du risque financier de la maladie chez une ...

    African Journals Online (AJOL)

    Il n'existe pas de différence entre l'adhésion à des systèmes de protection contre le risque financier face à la maladie (p>0,05). Les hommes considèrent la maladie comme un mal dans le corps (38%), les femmes la renvoient à une souffrance (58%). Les hommes ont une définition de la santé plus proche de celle de l'OMS ...

  11. Profile of Low Vision Population Attending Low Vision Clinic in a Peripheral Eye Hospital in Nepal

    OpenAIRE

    Safal Khanal, BOptom; Pekila Lama, MD

    2013-01-01

    Background: Blindness and low vision are major causes of morbidity and constitute a significant public health problem, both detrimental to the quality of life for the individual and an economic burden on the individual, family, and society in general. People with low vision have the potential for enhancement of functional vision if they receive the appropriate low vision services. The present study aims to determine the profile of the low vision population attending a low vision clinic at a p...

  12. Introducing Backchannel Technology into a Large Undergraduate Course | Introduction d’une technologie d’arrière-plan dans un vaste cours de premier cycle

    Directory of Open Access Journals (Sweden)

    Ruth Neustifter

    2016-04-01

    Full Text Available Backchannel technology can be used to allow students in large lecture courses to communicate with each other and the instructor during the delivery of lecture content and class discussions. It can also be utilized by instructors to capture, summarize, and integrate student questions, ideas, and needs into course content both immediately and throughout the course. The authors integrated backchannel software in one of two sections of a course, leaving the other section as a control; combined, the two sections contained a total number of 871 students. Data was gathered comparing both groups using online surveys and semester grades; results showed that the section using backchannel software had higher class satisfaction and perception of engagement, used their mobile devices more for accessing class content, felt more comfortable participating in class discussions, and had a higher grade average than the section that did not. The authors also explore their own experiences of finding, integrating, and maintaining backchannel technology. La technologie d’arrière-plan peut permettre aux étudiants de grands cours magistraux de communiquer les uns avec les autres et avec l’instructeur durant le cours et les discussions en classe. Les instructeurs peuvent aussi l’utiliser pour saisir, résumer et intégrer les questions, idées et besoins des étudiants dans le contenu du cours, et ce, immédiatement et pendant toute la durée du cours. Les auteurs ont intégré un logiciel d’arrière-plan dans l’une des deux sections d’un cours, faisant de l’autre section son groupe témoin. Ensemble, les deux sections comprenaient 871 étudiants. Des données ont été recueillies pour comparer les deux groupes à l’aide de sondages en ligne et des notes du trimestre. Les résultats ont démontré que la section utilisant le logiciel d’arrière-plan avait une plus grande satisfaction et une meilleure perception de l’engagement, que ses

  13. S'adapter à une nouvelle réalité environnementale au Maroc | CRDI ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    environnement ne cessent d'avoir une incidence sur le Maroc, un projet financé par le CRDI aide les populations à innover afin de survivre. Cet article fait partie d'une série de reportages sur des projets innovants mis en oeuvre ...

  14. Learning from vision-to-touch is different than from touch-to-vision.

    Directory of Open Access Journals (Sweden)

    Dagmar A Wismeijer

    2012-11-01

    Full Text Available We studied whether vision can teach touch to the same extent as touch seems to teach vision. In a 2 x 2 between-participants learning study, we artificially correlated visual gloss cues with haptic compliance cues. In two "natural" tasks, we tested whether visual gloss estimations have an influence on haptic estimations of softness and vice versa. In two "new" tasks, in which participants were either asked to haptically judge glossiness or to visually judge softness, we investigated how perceptual estimates transfer from one sense to the other. Our results showed that vision does not teach touch as efficient as touch seems to teach vision.

  15. Echographie devant une metrorragie du premier trimestre de ...

    African Journals Online (AJOL)

    Echographie devant une metrorragie du premier trimestre de grossesse sur uterus bicorne a issue favorable. Vaginal bleeding in a pregnant woman with a bicornuate uterus, ultrasound finding and favourable outcome.

  16. Frontoparietal cortex mediates perceptual transitions in bistable perception.

    Science.gov (United States)

    Weilnhammer, Veith A; Ludwig, Karin; Hesselmann, Guido; Sterzer, Philipp

    2013-10-02

    During bistable vision, perception oscillates between two mutually exclusive percepts despite constant sensory input. Greater BOLD responses in frontoparietal cortex have been shown to be associated with endogenous perceptual transitions compared with "replay" transitions designed to closely match bistability in both perceptual quality and timing. It has remained controversial, however, whether this enhanced activity reflects causal influences of these regions on processing at the sensory level or, alternatively, an effect of stimulus differences that result in, for example, longer durations of perceptual transitions in bistable perception compared with replay conditions. Using a rotating Lissajous figure in an fMRI experiment on 15 human participants, we controlled for potential confounds of differences in transition duration and confirmed previous findings of greater activity in frontoparietal areas for transitions during bistable perception. In addition, we applied dynamic causal modeling to identify the neural model that best explains the observed BOLD signals in terms of effective connectivity. We found that enhanced activity for perceptual transitions is associated with a modulation of top-down connectivity from frontal to visual cortex, thus arguing for a crucial role of frontoparietal cortex in perceptual transitions during bistable perception.

  17. Choc hémorragique suite à une ponction biopsie rénale (PBR): à ...

    African Journals Online (AJOL)

    Nous rapportons l'observation d'un patient âgé de 27 ans ayant bénéficié d'une PBR pour un diagnostic étiologique d'une insuffisance rénale aigue, l'évolution après la biopsie a été marquée par l'installation d'un choc hémorragique d'où la prise en charge en réanimation avec une néphrectomie d'hémostase. Pan African ...

  18. Une sémiotique à refaire?

    Directory of Open Access Journals (Sweden)

    Eric Landowski

    2013-12-01

    Full Text Available Le récit, c’est ce qui nous sert à donner un peu de signification et de valeur à la vie, en dépit de ce qu’elle peut avoir d’insignifiant par sa monotonie ou d’insensé par son aspect chaotique. Mais indépendamment des significations portées les récits, il nous arrive parfois, face à autrui, à une oeuvre, à un paysage, d’être saisis par la présence d’un sens qui s’impose à notre intuition bien qu’il n’émane d’aucun discours constitué. Ce sens second, toute une littérature, de Proust à Musil, de Svevo à Woolf, s’est employée à le dire en inventant les formes d’écriture de ce qu’on peut appeler le discours de l’expérience. Distinct du vécu, ce discours a le pouvoir d’en capter le mouvement en restituant la dynamique du rapport aux choses, à autrui, à soi-même sur laquelle se fonde l’expérience du sens dans son émergence en acte. Pour construire une sémiotique qui permette d’en rendre compte, ni la grammaire narrative standard ni ses prolongements relatifs aux passions et à la tensivité ne fournissent les instruments nécessaires. Il convient donc de compléter l’appareil théorique dont nous disposons. C’est ce qui justifie le réexamen critique des notions de narrativité et de discursivité auquel procède cet article, ainsi que la proposition finale d’un modèle tenant compte de la diversité des régimes possibles de production du sens dans l’interaction.

  19. Le contrôle de gestion environnementale d'une entreprise

    OpenAIRE

    Marquet-Pondeville, Sophie

    2001-01-01

    Dans cette recherche, nous étudions comment s’opère le contrôle de gestion environnementale. Cette problématique est abordée dans une perspective contingente et nous proposons un modèle théorique qui met en évidence l’impact de certaines variables sur les systèmes de contrôle de la gestion environnementale. Certains liens présents dans ce modèle sont discutés à travers une étude de cas.

  20. Neurorétinite unilatérale: une manifestation rare du syndrome post streptococcique

    Science.gov (United States)

    Iferkhass, Said; Elkhoyaali, Adil; Elasri, Fouad; Reda, Karim; Laktaoui, Abdelkader; Oubaaz, Abdelbar

    2014-01-01

    La streptocoque β hémolytique est responsable de plusieurs complications d'origine immunitaire, de localisation cardiaque, articulaire, dermatologique, rénale, cérébrale et oculaire. Nous rapportons le premier cas au Maroc d'une uvéite postérieure unilatérale post- streptococcique présentant une vascularite rétinienne avec œdème papillaire et des hémorragies rétiniennes en tache profondes et superficielles. Notre patient âgé de 56 ans, ayant comme antécédents pathologiques une notion d'angine et d’ érythème noueux à répétition d'origine streptococcique. Le bilan étiologique d'uvéite est revenu normal. En revanche, le titrage des anticorps antistreptococciques était significativement élevé: 430 IU /ml. Le patient a été mis sous amoxicilline protégée à une dose de 2 g par jour pendant 10 jours, associée à une corticothérapie à dose régressive sur un mois. L’évolution était favorable avec récupération totale de l'acuité visuelle (AV) et disparition des lésions neurorétiniennes PMID:25745528

  1. Haïti-Quisqueya: une double insularité

    Directory of Open Access Journals (Sweden)

    Jean-Marie THÉODAT

    1998-09-01

    Full Text Available Deux pays se partagent une île coupée par une frontière méridienne de plus de 300 km: Haïti à l'ouest, Quisqueya à l'est. Cette coupure est l'héritage du partage colonial de l'île entre la France et l'Espagne, et le résultat de la dynamique spatiale contrastée des deux nations qui y sont nées et qui ont eu recours à des principes d'encadrement distincts.De là un sentiment de double insularité, chaque pays se comportant vis-à-vis de son voisin comme s'ils étaient situés sur deux îles séparées.

  2. Top-down control of visual perception: attention in natural vision.

    Science.gov (United States)

    Rolls, Edmund T

    2008-01-01

    Top-down perceptual influences can bias (or pre-empt) perception. In natural scenes, the receptive fields of neurons in the inferior temporal visual cortex (IT) shrink to become close to the size of objects. This facilitates the read-out of information from the ventral visual system, because the information is primarily about the object at the fovea. Top-down attentional influences are much less evident in natural scenes than when objects are shown against blank backgrounds, though are still present. It is suggested that the reduced receptive-field size in natural scenes, and the effects of top-down attention contribute to change blindness. The receptive fields of IT neurons in complex scenes, though including the fovea, are frequently asymmetric around the fovea, and it is proposed that this is the solution the IT uses to represent multiple objects and their relative spatial positions in a scene. Networks that implement probabilistic decision-making are described, and it is suggested that, when in perceptual systems they take decisions (or 'test hypotheses'), they influence lower-level networks to bias visual perception. Finally, it is shown that similar processes extend to systems involved in the processing of emotion-provoking sensory stimuli, in that word-level cognitive states provide top-down biasing that reaches as far down as the orbitofrontal cortex, where, at the first stage of affective representations, olfactory, taste, flavour, and touch processing is biased (or pre-empted) in humans.

  3. Statistical regularities in art: Relations with visual coding and perception.

    Science.gov (United States)

    Graham, Daniel J; Redies, Christoph

    2010-07-21

    Since at least 1935, vision researchers have used art stimuli to test human response to complex scenes. This is sensible given the "inherent interestingness" of art and its relation to the natural visual world. The use of art stimuli has remained popular, especially in eye tracking studies. Moreover, stimuli in common use by vision scientists are inspired by the work of famous artists (e.g., Mondrians). Artworks are also popular in vision science as illustrations of a host of visual phenomena, such as depth cues and surface properties. However, until recently, there has been scant consideration of the spatial, luminance, and color statistics of artwork, and even less study of ways that regularities in such statistics could affect visual processing. Furthermore, the relationship between regularities in art images and those in natural scenes has received little or no attention. In the past few years, there has been a concerted effort to study statistical regularities in art as they relate to neural coding and visual perception, and art stimuli have begun to be studied in rigorous ways, as natural scenes have been. In this minireview, we summarize quantitative studies of links between regular statistics in artwork and processing in the visual stream. The results of these studies suggest that art is especially germane to understanding human visual coding and perception, and it therefore warrants wider study. Copyright 2010 Elsevier Ltd. All rights reserved.

  4. Biofeedback for Better Vision

    Science.gov (United States)

    1990-01-01

    Biofeedtrac, Inc.'s Accommotrac Vision Trainer, invented by Dr. Joseph Trachtman, is based on vision research performed by Ames Research Center and a special optometer developed for the Ames program by Stanford Research Institute. In the United States, about 150 million people are myopes (nearsighted), who tend to overfocus when they look at distant objects causing blurry distant vision, or hyperopes (farsighted), whose vision blurs when they look at close objects because they tend to underfocus. The Accommotrac system is an optical/electronic system used by a doctor as an aid in teaching a patient how to contract and relax the ciliary body, the focusing muscle. The key is biofeedback, wherein the patient learns to control a bodily process or function he is not normally aware of. Trachtman claims a 90 percent success rate for correcting, improving or stopping focusing problems. The Vision Trainer has also proved effective in treating other eye problems such as eye oscillation, cross eyes, and lazy eye and in professional sports to improve athletes' peripheral vision and reaction time.

  5. Grandeurs caractéristiques de la machine synchrone obtenues analytiquement à partir d'une réduction de modèle par une technique des multiéchelles de temps

    OpenAIRE

    Guesbaoui , H.

    1995-01-01

    Il est bien connu qu'il n'est pas possible d'avoir une écriture simple des courants et des tensions pour une machine synchrone modélisée par plus d'un amortisseur par axe d et q de Park. De plus, seules des méthodes numériques permettent un calcul approché de ses grandeurs caractéristiques. Dans cet article nous proposons de déterminer les constantes de temps sous une forme analytique à partir de l'écriture de sous-systèmes réduits du premier ordre décrivant les régimes subtransitoire, transi...

  6. Low Vision Rehabilitation and Diabetic Retinopathy

    International Nuclear Information System (INIS)

    Khan, Sarfaraz A.

    2007-01-01

    Diabetic retinopathy is emerging as a major cause of blindness. Diabetic retinopathy calls for a multidisciplinary to the patients. Management of the patient requires a team work by the internist, diabetologist, dietician, ophthalmologist and low vision therapist. Diabetic retinopathy very often results in vision loss. It is important for ophthalmologist to recognize the importance of low vision rehabilitation in formulating appropriate treatment strategies. People with low vision loss due to diabetic retinopathy usually experience difficulty in daily life. Most people with diabetic retinopathy (who have remaining useful vision) can be helped with low vision devices. However, often one low vision device may not be suitable for all purposes. A comprehensive low vision evaluation is required to assess the person's current visual status, identify the goals and the visual needs, and then design an individualized vision rehabilitation program to meet these needs. (author)

  7. Computer-enhanced stereoscopic vision in a head-mounted operating binocular

    International Nuclear Information System (INIS)

    Birkfellner, Wolfgang; Figl, Michael; Matula, Christian; Hummel, Johann; Hanel, Rudolf; Imhof, Herwig; Wanschitz, Felix; Wagner, Arne; Watzinger, Franz; Bergmann, Helmar

    2003-01-01

    Based on the Varioscope, a commercially available head-mounted operating binocular, we have developed the Varioscope AR, a see through head-mounted display (HMD) for augmented reality visualization that seamlessly fits into the infrastructure of a surgical navigation system. We have assessed the extent to which stereoscopic visualization improves target localization in computer-aided surgery in a phantom study. In order to quantify the depth perception of a user aiming at a given target, we have designed a phantom simulating typical clinical situations in skull base surgery. Sixteen steel spheres were fixed at the base of a bony skull, and several typical craniotomies were applied. After having taken CT scans, the skull was filled with opaque jelly in order to simulate brain tissue. The positions of the spheres were registered using VISIT, a system for computer-aided surgical navigation. Then attempts were made to locate the steel spheres with a bayonet probe through the craniotomies using VISIT and the Varioscope AR as a stereoscopic display device. Localization of targets 4 mm in diameter using stereoscopic vision and additional visual cues indicating target proximity had a success rate (defined as a first-trial hit rate) of 87.5%. Using monoscopic vision and target proximity indication, the success rate was found to be 66.6%. Omission of visual hints on reaching a target yielded a success rate of 79.2% in the stereo case and 56.25% with monoscopic vision. Time requirements for localizing all 16 targets ranged from 7.5 min (stereo, with proximity cues) to 10 min (mono, without proximity cues). Navigation error is primarily governed by the accuracy of registration in the navigation system, whereas the HMD does not appear to influence localization significantly. We conclude that stereo vision is a valuable tool in augmented reality guided interventions. (note)

  8. Fisiologia da visão binocular Physiology of binocular vision

    Directory of Open Access Journals (Sweden)

    Harley E. A. Bicas

    2004-02-01

    Full Text Available A visão binocular de seres humanos resulta da superposição quase completa dos campos visuais de cada olho, o que suscita discriminação perceptual de localizações espaciais de objetos relativamente ao observador (localização egocêntrica bem mais fina (estereopsia, mas isso ocorre em, apenas, uma faixa muito estreita (o horóptero. Aquém e além dela, acham-se presentes diplopia e confusão, sendo necessária supressão fisiológica (cortical para evitá-las. Analisa-se a geometria do horóptero e suas implicações fisiológicas (o desvio de Hillebrand, a partição de Kundt, a área de Panum, assim como aspectos clínicos da visão binocular normal (percepção simultânea, fusão, visão estereoscópica e de adaptações a seus estados afetados (supressão patológica, ambliopia, correspondência visual anômala.The binocular vision of human beings is given by the almost complete superimposition of the monocular visual fields, which allows a finer perceptual discrimination of the egocentric localization of objects in space (stereopsis but only within a very narrow band (the horopter. Before and beyond it, diplopia and confusion are present, so that a physiologic (cortical suppression is necessary to avoid them to become conscious. The geometry of the horopter and its physiologic implications (Hillebrand's deviation, Kundt's partition, Panum's area, stereoscopic vision are analyzed, as well as some clinical aspects of the normal binocular vision (simultaneous perception, fusion, stereoscopic vision and of adaptations to abnormal states (pathologic suppression, amblyopia, abnormal retinal correspondence.

  9. Perception of illusory contour figures: Microgenetic analysis

    Directory of Open Access Journals (Sweden)

    Gvozdenović Vasilije P.

    2004-01-01

    Full Text Available Microgenetic analysis was used to investigate perception of illusory contour figures which represent whole, completed forms on the basis of segmented, incomplete stimulation. The analysis provided an experimental approach to this phenomenon which was standardly investigated phenomenologically. Experimental procedure consisted of two phases: a priming phase and b test phase which consisted of visual search task. Two types of visual search tasks were applied: (i classic detection, in which subjects were detecting presence or absence of the target stimuli and (ii two-alternative forced choice, 2AFC, in which subjects performed discrimination between two concurrent targets (target A vs. target B. Variation of exposition of prim stimuli was used as an indication of the percept formation period. Concepts like early vision, visual attention and feature binding were investigated. Four experiments were conducted. Their outcome showed that (i perception of amodal figure requires visual attention, (ii features binding precedes spatial attention and (iii time period of percept formation is dependent of task properties and varies between 50 - 150 ms. Some results obtained in this research could be explained by feature-integration theory (Treisman & Gelade, 1980; Treisman, 1986. Furthermore, percept formation period data comply with data acquired in Elliott & Müller's psychophysical research (1998.

  10. Les écrits professionnels des enseignants : une approche didactique exploratoire

    Directory of Open Access Journals (Sweden)

    Rouba Hassan

    2012-07-01

    Full Text Available Cet article rend compte d’une étude effectuée au sein d’une recherche sur les écrits professionnels des enseignants (DAUNAY, 2011 dans une perspective didactique. Le but de cette recherche était de contribuer à mieux identifier cet objet désigné par « écrits professionnels » en explorant la diversité, la nature et les fonctions des écrits que produisent les enseignants dans le cadre de leur travail. L’étude présentée ici, qui se base sur des entretiens avec des enseignants du primaire et du secondaire et des observations dans leurs classes, montre que ces écrits sont inhérents à l’accomplissement des différentes tâches (BARRERE, 2002 du travail enseignant. L’analyse qui articule une analyse des écrits à un cadre sociologique et didactique (SCHNEUWLY, 2000 de l’analyse du travail enseignant montre la prégnance de deux types d’écrits : les écrits organisationnels et les écrits communicationnels (LACOSTE, 2001 qui s’opposent à bien des égards. La mise au jour des fonctions de ces écrits dans leurs liens aux tâches du métier apporte un éclairage nouveau sur les tensions qui traversent le métier d’enseignant.Mots-clés : Ecrit professionnel. Didactique. Tâches. Métier. Enseignant.

  11. The Relationship Between Fusion, Suppression, and Diplopia in Normal and Amblyopic Vision.

    Science.gov (United States)

    Spiegel, Daniel P; Baldwin, Alex S; Hess, Robert F

    2016-10-01

    Single vision occurs through a combination of fusion and suppression. When neither mechanism takes place, we experience diplopia. Under normal viewing conditions, the perceptual state depends on the spatial scale and interocular disparity. The purpose of this study was to examine the three perceptual states in human participants with normal and amblyopic vision. Participants viewed two dichoptically separated horizontal blurred edges with an opposite tilt (2.35°) and indicated their binocular percept: "one flat edge," "one tilted edge," or "two edges." The edges varied with scale (fine 4 min arc and coarse 32 min arc), disparity, and interocular contrast. We investigated how the binocular interactions vary in amblyopic (visual acuity [VA] > 0.2 logMAR, n = 4) and normal vision (VA ≤ 0 logMAR, n = 4) under interocular variations in stimulus contrast and luminance. In amblyopia, despite the established sensory dominance of the fellow eye, fusion prevails at the coarse scale and small disparities (75%). We also show that increasing the relative contrast to the amblyopic eye enhances the probability of fusion at the fine scale (from 18% to 38%), and leads to a reversal of the sensory dominance at coarse scale. In normal vision we found that interocular luminance imbalances disturbed binocular combination only at the fine scale in a way similar to that seen in amblyopia. Our results build upon the growing evidence that the amblyopic visual system is binocular and further show that the suppressive mechanisms rendering the amblyopic system functionally monocular are scale dependent.

  12. Novel compact panomorph lens based vision system for monitoring around a vehicle

    Science.gov (United States)

    Thibault, Simon

    2008-04-01

    Automotive applications are one of the largest vision-sensor market segments and one of the fastest growing ones. The trend to use increasingly more sensors in cars is driven both by legislation and consumer demands for higher safety and better driving experiences. Awareness of what directly surrounds a vehicle affects safe driving and manoeuvring of a vehicle. Consequently, panoramic 360° Field of View imaging can contributes most to the perception of the world around the driver than any other sensors. However, to obtain a complete vision around the car, several sensor systems are necessary. To solve this issue, a customized imaging system based on a panomorph lens will provide the maximum information for the drivers with a reduced number of sensors. A panomorph lens is a hemispheric wide angle anamorphic lens with enhanced resolution in predefined zone of interest. Because panomorph lenses are optimized to a custom angle-to-pixel relationship, vision systems provide ideal image coverage that reduces and optimizes the processing. We present various scenarios which may benefit from the use of a custom panoramic sensor. We also discuss the technical requirements of such vision system. Finally we demonstrate how the panomorph based visual sensor is probably one of the most promising ways to fuse many sensors in one. For example, a single panoramic sensor on the front of a vehicle could provide all necessary information for assistance in crash avoidance, lane tracking, early warning, park aids, road sign detection, and various video monitoring views.

  13. Caracterisation sociodemographique, clinique et criminologique d?une population de 210 meurtriers

    OpenAIRE

    2009-01-01

    Resume Cet article, de nature essentiellement descriptive, interroge les caracteristiques sociodemographiques, cliniques et criminologiques d?une population de 210 meurtriers examines par deux experts psychiatres angevins pendant une periode de 30 ans. Les meurtriers de notre serie sont majoritairement des hommes (73 %) d?age jeune, 33 ans en moyenne, sans emploi (51 %), vivant seuls au moment des faits (49 %). Ils ont des antecedents psychiatriques dans deux tiers des cas et des a...

  14. Une santé branchée

    International Development Research Centre (IDRC) Digital Library (Canada)

    C'est cette démarche qui a permis d'inventer le moteur à réaction, d'obtenir la ...... Ils ont démontré que les maladies transmissibles sont à l'origine de 59 p. ..... Le sida est à la fois un problème social et une affection biologique; on ne peut en ...

  15. Visual perception and memory systems: from cortex to medial temporal lobe.

    Science.gov (United States)

    Khan, Zafar U; Martín-Montañez, Elisa; Baxter, Mark G

    2011-05-01

    Visual perception and memory are the most important components of vision processing in the brain. It was thought that the perceptual aspect of a visual stimulus occurs in visual cortical areas and that this serves as the substrate for the formation of visual memory in a distinct part of the brain called the medial temporal lobe. However, current evidence indicates that there is no functional separation of areas. Entire visual cortical pathways and connecting medial temporal lobe are important for both perception and visual memory. Though some aspects of this view are debated, evidence from both sides will be explored here. In this review, we will discuss the anatomical and functional architecture of the entire system and the implications of these structures in visual perception and memory.

  16. Beauty and cuteness in peripheral vision

    Science.gov (United States)

    Kuraguchi, Kana; Ashida, Hiroshi

    2015-01-01

    Guo et al. (2011) showed that attractiveness was detectable in peripheral vision. Since there are different types of attractiveness (Rhodes, 2006), we investigated how beauty and cuteness are detected in peripheral vision with a brief presentation. Participants (n = 45) observed two Japanese female faces for 100 ms, then were asked to respond which face was more beautiful (or cuter). The results indicated that both beauty and cuteness were detectable in peripheral vision, but not in the same manner. Discrimination rates for judging beauty were invariant in peripheral and central vision, while discrimination rates for judging cuteness declined in peripheral vision as compared with central vision. This was not explained by lower resolution in peripheral vision. In addition, for male participants, it was more difficult to judge cuteness than beauty in peripheral vision, thus suggesting that gender differences can have a certain effect when judging cuteness. Therefore, central vision might be suitable for judging cuteness while judging beauty might not be affected by either central or peripheral vision. This might be related with the functional difference between beauty and cuteness. PMID:25999883

  17. Une Cyathura cavernicole nouvelle de Sarawak – Kalimantan du Nord (Isopoda, Anthuridae)

    NARCIS (Netherlands)

    Andreev, Stoitze

    1982-01-01

    A l’occasion d’une expédition spéléologique effectuée en 1978 à Sarawak et organisée par la Royal Geographical Society, le biospéléologue anglais Dr. Ph. Chapman a recueilli quelques exemplaires d’un Isopode des eaux douces souterraines, appartenant à une nouvelle espèce du genre Cyathura. La

  18. The contribution of single case studies to the neuroscience of vision.

    Science.gov (United States)

    Zihl, Josef; Heywood, Charles A

    2016-03-01

    Visual neuroscience is concerned with the neurobiological foundations of visual perception, that is, the morphological, physiological, and functional organization of the visual brain and its co-operative partners. One important approach for understanding the functional organization of the visual brain is the study of visual perception from the pathological perspective. The study of patients with focal injury to the visual brain allows conclusions about the representation of visual perceptual functions in the framework of association and dissociation of functions. Selective disorders have been reported for more "elementary" visual capabilities, for example, color and movement vision, but also for visuo-cognitive capacities, such as visual agnosia or the visual field of attention. Because these visual disorders occur rather seldom as selective and specific dysfunctions, single cases have always played, and still play, a significant role in gaining insights into the functional organization of the visual brain. © 2016 The Institute of Psychology, Chinese Academy of Sciences and John Wiley & Sons Australia, Ltd.

  19. Jérôme Glicenstein, L’art : une histoire d’expositions

    Directory of Open Access Journals (Sweden)

    Olivier le Falher

    2010-04-01

    Full Text Available L’ouvrage est fondé sur une critique de la philosophie et de l'histoire de l'art qui auraient négligé ce que les oeuvres doivent aux formes de monstration qui les font accéder à une existence publique : « les sciences de l'art se sont plutôt structurées sur l’idée d'une valorisation des oeuvres – c’est-à-dire des objets – et des artistes au détriment de la façon dont ils étaient présentés dans l’espace public » (p. 221. L’enjeu de cet ouvrage consiste donc à déplacer le regard depuis l’oeuvr...

  20. Pascale Antolin-Pires. L’Objet et ses doubles. Une relecture de Fitzgerald.

    Directory of Open Access Journals (Sweden)

    Marie-Agnès Gay

    2006-04-01

    Full Text Available Ce n’est pas le moindre mérite de cet ouvrage que de tenir le pari affiché dans son titre, à savoir nous entraîner en effet dans une « relecture » de Fitzgerald. La référence aux objets évoque certes la dimension mimétique du texte fitzgeraldien, si souvent réduit à un documentaire sur le Jazz Age ; mais l’auteur, en traquant les doubles ou faux sens de ces objets-signes présente l’envers de cette œuvre qui, plutôt que d’une tradition réaliste fondée sur le mode référentiel, relève d’une écri...

  1. Blocage de Coulomb dans une boite quantique laterale contenant un faible nombre d'electrons

    Science.gov (United States)

    Gould, Charles

    Dans ce travail on utilise une nouvelle geometrie pour augmenter le controle sur le nombre d'electrons contenus dans une boite quantique laterale, et ainsi atteindre un regime de petit nombre d'electrons. Ces echantillons permettent une etude du blocage de Coulomb quand les electrons sont injectes a partir d'un gaz electronique a deux dimensions (2DEG). Les mesures a faible champ magnetique demontrent la grande flexibilite des echantillons et montrent que l'on peut faire varier le nombre d'electrons dans une boite quantique a partir de plus de 40 electrons jusqu'a un seul electron, ce qui est assez courant dans les boites quantiques verticales, mais ce qui n'avait jamais ete reussi dans une boite quantique laterale. Nos resultats montrent egalement que dans les boites quantiques laterales il est possible de determiner le spin du niveau qui participe au transport a l'aide du phenomene de blocage de spin. De plus, dans certaines circonstances il est meme possible de determiner le spin total de la boite quantique, ce qui peut avoir des applications pratiques dans des domaines tels l'informatique quantique. Les mesures dans le regime de renversement de spin a un champ magnetique plus eleve montrent l'importance des correlations electrons---electrons dans ces boites quantiques, qui menent a des depolarisations et a des structures de spins qui ont un effet sur le transport. En particulier, ces correlations menent a l'existence de niveaux excites de basse energie qui causent une dependance anormale de l'amplitude des pics de blocage de Coulomb en fonction de la temperature. Nos experiences demontrent egalement la possibilite d'utiliser ces boites quantiques comme sondes pour etudier les proprietes du bord d'un 2DEG. Une voie de recherche a etre exploree.

  2. Efficacy of vision therapy in children with learning disability and associated binocular vision anomalies.

    Science.gov (United States)

    Hussaindeen, Jameel Rizwana; Shah, Prerana; Ramani, Krishna Kumar; Ramanujan, Lalitha

    To report the frequency of binocular vision (BV) anomalies in children with specific learning disorders (SLD) and to assess the efficacy of vision therapy (VT) in children with a non-strabismic binocular vision anomaly (NSBVA). The study was carried out at a centre for learning disability (LD). Comprehensive eye examination and binocular vision assessment was carried out for 94 children (mean (SD) age: 15 (2.2) years) diagnosed with specific learning disorder. BV assessment was done for children with best corrected visual acuity of ≥6/9 - N6, cooperative for examination and free from any ocular pathology. For children with a diagnosis of NSBVA (n=46), 24 children were randomized to VT and no intervention was provided to the other 22 children who served as experimental controls. At the end of 10 sessions of vision therapy, BV assessment was performed for both the intervention and non-intervention groups. Binocular vision anomalies were found in 59 children (62.8%) among which 22% (n=13) had strabismic binocular vision anomalies (SBVA) and 78% (n=46) had a NSBVA. Accommodative infacility (AIF) was the commonest of the NSBVA and found in 67%, followed by convergence insufficiency (CI) in 25%. Post-vision therapy, the intervention group showed significant improvement in all the BV parameters (Wilcoxon signed rank test, p<0.05) except negative fusional vergence. Children with specific learning disorders have a high frequency of binocular vision disorders and vision therapy plays a significant role in improving the BV parameters. Children with SLD should be screened for BV anomalies as it could potentially be an added hindrance to the reading difficulty in this special population. Copyright © 2017 Spanish General Council of Optometry. Published by Elsevier España, S.L.U. All rights reserved.

  3. Synthetic vision to augment sensor based vision for remotely piloted vehicles

    NARCIS (Netherlands)

    Tadema, J.; Koeners, J.; Theunissen, E.

    2006-01-01

    In the past fifteen years, several research programs have demonstrated potential advantages of synthetic vision technology for manned aviation. More recently, some research programs have focused on integrating synthetic vision technology into control stations for remotely controlled aircraft. The

  4. Une méthode pour estimer l’interception du rayonnement par un couvert bas : application au colza avant montaison

    Directory of Open Access Journals (Sweden)

    Denoroy Pascal

    2002-01-01

    Full Text Available Dans les modèles de simulation du fonctionnement des cultures, l’interception du rayonnement est une variable cruciale pour la prévision de la productivité en biomasse. D’autre part, la connaissance de l’interception du rayonnement par une culture permet de mieux analyser la réponse à un traitement en autorisant la distinction entre les effets morphogénétique et physiologique du traitement. Par exemple, dans l’étude de la fertilisation azotée du colza [1] on a pu faire la part de l’effet morphogénétique (accroissement de l’indice foliaire, donc de l’interception et de l’amélioration de la conversion photosynthétique du rayonnement absorbé. Dans un cas comme dans l’autre, une estimation correcte de l’interception du rayonnement est essentielle. Très souvent, un formalisme dérivé de la loi de Beer-Lambert est utilisé pour quantifier la part interceptée du rayonnement : PARi = epsiloni PAR (1 et epsiloni = 1 - e- k.IF (2, PAR représentant le rayonnement photosynthétiquement actif incident (exprimé en Joules ou en moles de photons, PARi la part de ce dernier interceptée par le couvert, epsiloni le coefficient (sans dimension d’interception, IF l’indice foliaire et k le coefficient d’extinction du rayonnement. Un formalisme un peu plus complexe doit être utilisé si on veut considérer le rayonnement absorbé [1, 2]. Pour des cultures couvrantes, la sensibilité de ces modèles à la valeur de k est faible pour les IF élevés, c’est pourquoi ces modèles sont souvent utilisés avec succès. Mais aux faibles IF, les modèles sont sensibles à k, d’où l’importance de l’estimation de ce paramètre pour les cultures présentant une longue période de faible couverture du sol, tel le colza peu fertilisé en phase hivernale. De plus, pour les cultures discontinues, c’est-à-dire présentant des zones où le sol n’est pas du tout couvert par la végétation, comme les inter-rangs, on doit

  5. PEDAGOGIE PAR PROJET: UNE ÉTUDE DE CAS DANS L'ENSEIGNEMENT SUPERIEUR TECHNOLOGIQUE

    Directory of Open Access Journals (Sweden)

    Ngo van Thien

    Full Text Available Cet article rapporte les résultats d'un questionnaire proposé aux étudiants d'une formation d'enseignement supérieur technologique en génie électrique et informatique industrielle. L'objectif de ce questionnaire est d'évaluer le profit que les étudiants ont retiré d'un enseignement des techniques de gestion de projet, et l'utilisation qu'ils en ont fait, d'une part au cours d'une série de travaux pratiques utilisant la pédagogie par projet, d'autre part au cours de leur stage de fin d'études en entreprise.

  6. Le sous-titrage : une pratique à la marge de la traduction

    Directory of Open Access Journals (Sweden)

    Dumas, Louise

    2014-12-01

    Full Text Available Le sous-titre interlinguistique est un objet difficile à appréhender théoriquement. S'il permet d'aller d'une langue à une autre, il implique aussi un passage de l'écoute à la lecture et du cinéma à l'écriture. Le caractère interlinguistique est souvent mis en avant pour amener à considérer le sous-titrage comme une traduction. Sa complexité médiologique suggère toutefois qu'il est plus qu'une traduction. En même temps, les fortes contraintes (exigence de brièveté, de lisibilité, de cohérence avec l'image cinématographique auxquelles il est soumis font qu'il est moins qu'une traduction – moins exact, moins long, moins « équivalent » au texte original. Le présent travail se propose de réfléchir de manière théorique aux rapports entre sous-titrage et traduction. Pour ce faire, nous confronterons le sous-titrage aux concepts fondamentaux de la traductologie. Premièrement, le passage de l'oral à l'écrit opéré dans les sous-titres est intimement lié à la distinction traductologique entre traduction et interprétariat. Pour pouvoir condenser les dialogues, résumer leur contenu, le sous-titreur est amené à les interpréter, ce qui permet de souligner l'étroite parenté entre traduction, interprétariat et interprétation. Deuxièmement, les fortes contraintes auxquelles sont soumis les sous-titres invitent à s'interroger sur la notion d'équivalence qui se trouve normalement au principe de toute traduction. Toutes les théories traductologiques insistent sur le fait qu'une équivalence n'est jamais parfaite et que le traducteur privilégie certains niveaux d'équivalence : en poussant à l'extrême cette dynamique de sélection constitutive de l'équivalence, on peut considérer que les sous-titres sont équivalents aux dialogues. En tant que cas limite, le sous-titrage permet de tester les concepts fondamentaux de la traductologie et de définir leurs limites.

  7. Intersection Recognition and Guide-Path Selection for a Vision-Based AGV in a Bidirectional Flow Network

    Directory of Open Access Journals (Sweden)

    Wu Xing

    2014-03-01

    Full Text Available Vision recognition and RFID perception are used to develop a smart AGV travelling on fixed paths while retaining low-cost, simplicity and reliability. Visible landmarks can describe features of shapes and geometric dimensions of lines and intersections, and RFID tags can directly record global locations on pathways and the local topological relations of crossroads. A topological map is convenient for building and editing without the need for accurate poses when establishing a priori knowledge of a workplace. To obtain the flexibility of bidirectional movement along guide-paths, a camera placed in the centre of the AGV looks downward vertically at landmarks on the floor. A small visual field presents many difficulties for vision guidance, especially for real-time, correct and reliable recognition of multi-branch crossroads. First, the region projection and contour scanning methods are both used to extract the features of shapes. Then LDA is used to reduce the number of the features' dimensions. Third, a hierarchical SVM classifier is proposed to classify their multi-branch patterns once the features of the shapes are complete. Our experiments in landmark recognition and navigation show that low-cost vision systems are insusceptible to visual noises, image breakages and floor changes, and a vision-based AGV can locate itself precisely on its paths, recognize different crossroads intelligently by verifying the conformance of vision and RFID information, and select its next pathway efficiently in a bidirectional flow network.

  8. What You Should Know (Low Vision)

    Science.gov (United States)

    ... Cataract Diabetic retinopathy Glaucoma Macular degeneration What is low vision? When you have low vision, eyeglasses, contact lenses, ... eyesight. How do I know if I have low vision? Below are some signs of low vision. Even ...

  9. Détermination d’une ligne de rivage de grande taille à l’aide de la multi résolution hiérarchique sur une image RSO

    Directory of Open Access Journals (Sweden)

    Alain Akono

    2007-07-01

    Full Text Available Le but de cette étude consiste à évaluer la longueur de la ligne de rivage sur une série d’images réduites par la technique de multi résolution hiérarchique, et extraites d’une image radar à synthèse d’ouverture (RSO ERS-1 de très grande taille, en utilisant la détection des contours et la morphologie mathématique. Les résultats obtenus sur les images réduites sont ensuite extrapolés pour permettre d’obtenir la longueur de la ligne de rivage sur l’image originale. La méthodologie présentée permet d’obtenir une bonne indication des longueurs de rivage à partir d’images satellitaires de grande taille, et elle est notamment utile au suivi de la dynamique de l’érosion côtière.

  10. Qualité de vie et consommation soutenable : une perspective pratique

    Directory of Open Access Journals (Sweden)

    Patrick Mardellat

    2010-06-01

    Full Text Available Ce texte tente de parvenir à une meilleure compréhension du rôle de la consommation relativement à l’objectif de soutenabilité de nos modes de vie. À cette fin, on croise deux thématiques : consommation et bonheur, consommation et soutenabilité. Les paradigmes standard et institutionnalistes de la consommation soutenable sont questionnés du point de vue de la tradition pratique – aristotélicienne – qui en montre les limites et les insuffisances. L’approche quantitative de la limitation de la consommation caractéristique de ces deux approches conduit à une impasse. La réception de cette notion de consommation soutenable dans la tradition pratique est ensuite esquissée, faisant apparaître l’existence d’une vertu propre à l’économie, d’un lieu et d’une institution de la consommation accueillis dans une constellation de régimes politiques possibles.This text aims to reach a better understanding of the role of consumption with regard to the objective of sustainability of our lifestyles. We cross two themes: consumption and happiness, consumption and sustainability. The standard and institutionalist paradigms of sustainable consumption are questioned parts from the viewpoint of the Aristotelian tradition which shows their limits and failures. The quantitative approach of the limitation of consumption specific of these two approaches leads to a dead end. Then the reception of this notion of sustainable consumption in the practical tradition is sketched. The existence of an appropriate virtue for the economy, a place and an institution of the consumption welcomed in a constellation of possible political regimes clearly appear as the keystones of the practical conception of sustainable consumption.  

  11. Evaluating private security sector market perceptions in Finland

    OpenAIRE

    Santonen, Teemu; Paasonen, Jyri

    2015-01-01

    The role and signifi cance of private security services have grown in many countries, since traditional tasks of security authorities are being outsourced. The goal of this study is to empirically evaluate the perceptions of the private security market in Finland. As a result, we identifi ed three different future scenarios for the Finnish private security market, including(1) international success via innovations, (2) success via domestic markets, and (3) pessimistic success vision. It appea...

  12. Analyse cognitive d'une politique publique : justice ...

    African Journals Online (AJOL)

    Analyse cognitive d'une politique publique : justice environnementale et « marchés ruraux » de bois-énergie. ... energy sources to poor urban dwellers; and to reduce the poverty of rural households by promoting sustainable forest management including income generation through producing and marketing charcoal.

  13. Difficultes d'une campagne de depistage du cancer du col uterin en ...

    African Journals Online (AJOL)

    ... on dénombrait 10 cas (20%) de Gadnerella, 3(6%) Candida et 2 (4%) Trichomonas. Au vu de ces résultats en zone rurale marqués notamment par une faible participation des femmes et un grand nombre de frottis inflammatoires, une approche révisée des moyens de campagne de dépistage des cancers est nécessaire, ...

  14. Une ONG sénégalaise renouvelle son engagement envers l ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    28 avr. 2016 ... Innovation, environnement et développement en Afrique (IED Afrique) est une organisation indépendante sans but lucratif établie au Sénégal qui, depuis une quinzaine d'années, intervient sur les problématiques de développement durable et de citoyenneté en Afrique de l'Ouest francophone. Créée en ...

  15. Apport de l’histopathologie dans le diagnostic d’une calcinose scrotale: a propos d’un cas

    Directory of Open Access Journals (Sweden)

    K. Doh

    2015-03-01

    Full Text Available La calcinose scrotale est une maladie rare, bénigne, de pathogénie incertaine caractérisée par de nombreux nodules indolores, durs du scrotum en absence de tout trouble métabolique systémique. Nous rapportons le cas d’un patient âgé de 57 ans qui présente une calcinose scrotale de découverte histologique fortuite associée à un eczéma chronique et une hernie inguinale gauche. Nous discutons après une revue de la littérature, les aspects pathogéniques, cliniques, thérapeutiques et anatomopathologiques de cette pathologie mal comprise.

  16. Autonomous Landing and Ingress of Micro-Air-Vehicles in Urban Environments Based on Monocular Vision

    Science.gov (United States)

    Brockers, Roland; Bouffard, Patrick; Ma, Jeremy; Matthies, Larry; Tomlin, Claire

    2011-01-01

    Unmanned micro air vehicles (MAVs) will play an important role in future reconnaissance and search and rescue applications. In order to conduct persistent surveillance and to conserve energy, MAVs need the ability to land, and they need the ability to enter (ingress) buildings and other structures to conduct reconnaissance. To be safe and practical under a wide range of environmental conditions, landing and ingress maneuvers must be autonomous, using real-time, onboard sensor feedback. To address these key behaviors, we present a novel method for vision-based autonomous MAV landing and ingress using a single camera for two urban scenarios: landing on an elevated surface, representative of a rooftop, and ingress through a rectangular opening, representative of a door or window. Real-world scenarios will not include special navigation markers, so we rely on tracking arbitrary scene features; however, we do currently exploit planarity of the scene. Our vision system uses a planar homography decomposition to detect navigation targets and to produce approach waypoints as inputs to the vehicle control algorithm. Scene perception, planning, and control run onboard in real-time; at present we obtain aircraft position knowledge from an external motion capture system, but we expect to replace this in the near future with a fully self-contained, onboard, vision-aided state estimation algorithm. We demonstrate autonomous vision-based landing and ingress target detection with two different quadrotor MAV platforms. To our knowledge, this is the first demonstration of onboard, vision-based autonomous landing and ingress algorithms that do not use special purpose scene markers to identify the destination.

  17. Active vision and image/video understanding with decision structures based on the network-symbolic models

    Science.gov (United States)

    Kuvich, Gary

    2003-08-01

    Vision is a part of a larger information system that converts visual information into knowledge structures. These structures drive vision process, resolve ambiguity and uncertainty via feedback projections, and provide image understanding that is an interpretation of visual information in terms of such knowledge models. The ability of human brain to emulate knowledge structures in the form of networks-symbolic models is found. And that means an important shift of paradigm in our knowledge about brain from neural networks to "cortical software". Symbols, predicates and grammars naturally emerge in such active multilevel hierarchical networks, and logic is simply a way of restructuring such models. Brain analyzes an image as a graph-type decision structure created via multilevel hierarchical compression of visual information. Mid-level vision processes like clustering, perceptual grouping, separation of figure from ground, are special kinds of graph/network transformations. They convert low-level image structure into the set of more abstract ones, which represent objects and visual scene, making them easy for analysis by higher-level knowledge structures. Higher-level vision phenomena are results of such analysis. Composition of network-symbolic models works similar to frames and agents, combines learning, classification, analogy together with higher-level model-based reasoning into a single framework. Such models do not require supercomputers. Based on such principles, and using methods of Computational intelligence, an Image Understanding system can convert images into the network-symbolic knowledge models, and effectively resolve uncertainty and ambiguity, providing unifying representation for perception and cognition. That allows creating new intelligent computer vision systems for robotic and defense industries.

  18. Vision Problems in Homeless Children.

    Science.gov (United States)

    Smith, Natalie L; Smith, Thomas J; DeSantis, Diana; Suhocki, Marissa; Fenske, Danielle

    2015-08-01

    Vision problems in homeless children can decrease educational achievement and quality of life. To estimate the prevalence and specific diagnoses of vision problems in children in an urban homeless shelter. A prospective series of 107 homeless children and teenagers who underwent screening with a vision questionnaire, eye chart screening (if mature enough) and if vision problem suspected, evaluation by a pediatric ophthalmologist. Glasses and other therapeutic interventions were provided if necessary. The prevalence of vision problems in this population was 25%. Common diagnoses included astigmatism, amblyopia, anisometropia, myopia, and hyperopia. Glasses were required and provided for 24 children (22%). Vision problems in homeless children are common and frequently correctable with ophthalmic intervention. Evaluation by pediatric ophthalmologist is crucial for accurate diagnoses and treatment. Our system of screening and evaluation is feasible, efficacious, and reproducible in other homeless care situations.

  19. Assessment of Color Vision Among School Children: A Comparative Study Between The Ishihara Test and The Farnsworth D-15 Test

    Directory of Open Access Journals (Sweden)

    Rajesh Kishor Shrestha

    2016-10-01

    Full Text Available Introduction: Color vision is one of the important attribute of visual perception. The study was conducted at different schools of Kathmandu to compare the  ndings of the Ishihara Pseudoisochromatic test and the Farnsworth D-15 test.  Method: A cross-sectional study was conducted among 2120 students of four schools of Kathmandu. Assessment included visual acuity measurement, slit lamp examination of anterior segment and fundus examination with direct ophthalmoscopy. Each student was assessed with the Ishihara pseudoisochromatic test and the Farnsworth D-15 test. The Chi-square test was performed to analyse color vision defect detected by the Ishihara test and the Farnsworth D-15 test. Results: A total of 2120 students comprising of 1114 males (52.5% and 1006 females (47.5% were recruited in the study with mean age of 12.2 years (SD 2.3 years. The prevalence of color vision defect as indicated by the Ishihara was 2.6 and as indicated by the D-15 test was 2.15 in males.  Conclusion: For school color vision screening, the Ishihara color test and the Farnsworth D-15 test have equal capacity to detect congenital color vision defect and they complement each other.  Keywords: color vision; children; defect; Farnsworth D-15; Ishihara.

  20. Déshumidification de l'air d'une serre par contact direct à courants croisés avec une solution hygroscopique organique

    Science.gov (United States)

    Chraibi, A.; Jaffrin, A.; Makhlouf, S.; Bentounes, N.

    1995-07-01

    Greenhouse air can be dehumidified by direct contact with a desicant fluid on a trickle exchanger. The water vapour extraction rate depends on the hygroscopicity of the fluid and on the exchanger efficiency. An organic fluid, the triethylene glycol (TEG) at 90% concentration, has been tested. Cross corrugated cellulosic pads, of the type used in cooling, irrigated with TEG, were placed in a wind channel to dehumidify air at various speeds and temperatures. A semi-analytical model, based on energy and mass conservation, correctly reproduces the water vapor extraction rate and the enthalpy change of both fluids. It is shown that TEG trickling through a ventilated pad of 1 m^2 area and 0.1 m thickness can be used to extract 3 to 5 kg of water vapor per hour in greenhouse climate control applications. Several pads arranged in series can be used to decrease more efficiently the absolute humidity of the air, for other applications like food drying or industrial compressed air. Une technique de déshumidification de l'air des serres consiste à le soumettre au contact d'une solution hygroscopique au sein d'un échangeur ruisselant. Le taux d'extraction de vapeur d'eau dépend à la fois du pouvoir hygroscopique de la solution et de l'efficacité de l'échangeur. Une solution hygroscopique organique, le triéthylène glycol à 90% de concentration, a été expérimentée. Un échangeur ruisselant constitué de parois de cellulose ondulées à corrugations croisées, du type “cooling pad” pour serres agricoles, a été testé pour déshumidifier de l'air dans une soufflerie expérimentale. Un modèle semi-analytique, basé sur les équations de conservation de l'énergie et de masse, permet de rendre compte des échanges et de déduire les paramètres de sortie des deux fluides en contact, à partir des caractéristiques d'entrée. Cette étude permet de chiffrer à environ 3 à 5kg/h la capacité de déshumidification d'un panneau d'un mètre carré et de 10cm d

  1. Une perspective interactionniste

    Directory of Open Access Journals (Sweden)

    Joëlle Morrissette

    2010-02-01

    Full Text Available Cet article vise à montrer l’intérêt de puiser à la sociologie pour conduire des recherches dans le domaine de l’éducation. Plus précisément, il sera question de la contribution d’une perspective interactionniste pour appréhender un objet attaché à l’évaluation des apprentissages des élèves. Comme on le verra, s’inspirer en particulier d’auteurs attachés à la tradition de l’interactionnisme symbolique amène à se situer en marge des manières de dire et de faire habituelles des investigations portant sur cet objet, de la phase de problématisation à celle de l’analyse, au profit d’un point de vue (resocialisant et contextualisant. Pour illustrer le propos, je prendrai appui sur le format d’une recherche ayant documenté le savoir-faire d’un groupe d’enseignantes du primaire en matière d’évaluation formative, et ayant adopté une perspective interactionniste comme posture générale de recherche.An Interactionist PerspectiveAn Alternative Approach to Learning AssessmentThis article aims to show the usefulness of drawing from sociology to conduct research in the field of education. Specifically, it discusses the contribution of an interactionist perspective in understanding the objects attached to student learning assessment. As we shall see, drawing especially from authors working in the tradition of Symbolic Interactionism leads us outside the usual ways of thinking and doing in investigations related to assessment objects, from problematization to analysis, in favour of a (resocializing and contextualizing perspective. To illustrate this point, I will examine the format of a study documenting the expertise of a group of elementary school teachers with regard to formative assessment, and having an interactionist perspective as its basis of research.Una perspectiva interaccionista: otro punto de vista sobre la evaluación del aprendizajeEste artículo tiene como objetivo el demostrar el interés de

  2. WiFi : Une nouvelle façon de combler le fossé numérique ? | CRDI ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    13 juil. 2011 ... Se brancher à Internet en utilisant une simple antenne faite d'aluminium et une carte de réseau sans fil! Voilà une façon de donner un nouvel élan au développement économique, explique M. Onno Purbo, spécialiste des technologies de l'information et des communications (TIC) basé à Jakarta qui était de ...

  3. Will Brazilian Patented Naturoptic Method for Recovery of Healthy Vision be Helpful Linguistically?

    Science.gov (United States)

    de Moraes, Ana Paula; Dos Santos Marques, Rosélia; Mc Leod, Roger David

    2008-10-01

    Naturoptics Inc. extends its patent(s) to further the teaching of vision-restoring process(es), foster cross-linguistic capabilities, and assist in the educational or financial opportunities of individuals and countries. Directors of Naturoptics Inc. hope to achieve this while testing David Matthew Mc Leod's observations that high visual acuity correlates with other mental and sensory processes. He and RDM often noticed that thought concepts (language percepts) are detectable even across species barriers, as when bears, moose, et c. made their intentions known to us in ways we were culturally willing to accept. This addresses aspects of language that seemed related to our understanding of human vision, and how it encodes cortically by spatial frequency content of a visual scene. Words representing the same meaning in two different languages will encode at precisely the same site in the visual cortex. Predictions: ``our memories,'' and cross-species, detection of certain thoughts, if equivalently ``seen'' as images, (spatial frequency content).

  4. Do vision and haptics share common representations? Implicit and explicit memory within and between modalities.

    Science.gov (United States)

    Easton, R D; Srinivas, K; Greene, A J

    1997-01-01

    Previous assessments of verbal cross-modal priming have typically been conducted with the visual and auditory modalities. Within-modal priming is always found to be substantially larger than cross-modal priming, a finding that could reflect modality modularity, or alternatively, differences between the coding of visual and auditory verbal information (i.e., geometric vs. phonological). The present experiments assessed implicit and explicit memory within and between vision and haptics, where verbal information could be coded in geometric terms. Because haptic perception of words is sequential or letter-by-letter, experiments were also conducted to isolate the effects of simultaneous versus sequential processing from the manipulation of modality. Together, the results reveal no effects of modality change on implicit or explicit tests. The authors discuss representational similarities between vision and haptics as well as image mediation as possible explanations for the results.

  5. Learning from vision-to-touch is different than learning from touch-to-vision.

    Science.gov (United States)

    Wismeijer, Dagmar A; Gegenfurtner, Karl R; Drewing, Knut

    2012-01-01

    We studied whether vision can teach touch to the same extent as touch seems to teach vision. In a 2 × 2 between-participants learning study, we artificially correlated visual gloss cues with haptic compliance cues. In two "natural" tasks, we tested whether visual gloss estimations have an influence on haptic estimations of softness and vice versa. In two "novel" tasks, in which participants were either asked to haptically judge glossiness or to visually judge softness, we investigated how perceptual estimates transfer from one sense to the other. Our results showed that vision does not teach touch as efficient as touch seems to teach vision.

  6. Adaptive Multi-Sensor Perception for Driving Automation in Outdoor Contexts

    Directory of Open Access Journals (Sweden)

    Annalisa Milella

    2014-08-01

    Full Text Available In this research, adaptive perception for driving automation is discussed so as to enable a vehicle to automatically detect driveable areas and obstacles in the scene. It is especially designed for outdoor contexts where conventional perception systems that rely on a priori knowledge of the terrain's geometric properties, appearance properties, or both, is prone to fail, due to the variability in the terrain properties and environmental conditions. In contrast, the proposed framework uses a self-learning approach to build a model of the ground class that is continuously adjusted online to reflect the latest ground appearance. The system also features high flexibility, as it can work using a single sensor modality or a multi-sensor combination. In the context of this research, different embodiments have been demonstrated using range data coming from either a radar or a stereo camera, and adopting self-supervised strategies where monocular vision is automatically trained by radar or stereo vision. A comprehensive set of experimental results, obtained with different ground vehicles operating in the field, are presented to validate and assess the performance of the system.

  7. IDA's Energy Vision 2050

    DEFF Research Database (Denmark)

    Mathiesen, Brian Vad; Lund, Henrik; Hansen, Kenneth

    IDA’s Energy Vision 2050 provides a Smart Energy System strategy for a 100% renewable Denmark in 2050. The vision presented should not be regarded as the only option in 2050 but as one scenario out of several possibilities. With this vision the Danish Society of Engineers, IDA, presents its third...... contribution for an energy strategy for Denmark. The IDA’s Energy Plan 2030 was prepared in 2006 and IDA’s Climate Plan was prepared in 2009. IDA’s Energy Vision 2050 is developed for IDA by representatives from The Society of Engineers and by a group of researchers at Aalborg University. It is based on state......-of-the-art knowledge about how low cost energy systems can be designed while also focusing on long-term resource efficiency. The Energy Vision 2050 has the ambition to focus on all parts of the energy system rather than single technologies, but to have an approach in which all sectors are integrated. While Denmark...

  8. Panoramic stereo sphere vision

    Science.gov (United States)

    Feng, Weijia; Zhang, Baofeng; Röning, Juha; Zong, Xiaoning; Yi, Tian

    2013-01-01

    Conventional stereo vision systems have a small field of view (FOV) which limits their usefulness for certain applications. While panorama vision is able to "see" in all directions of the observation space, scene depth information is missed because of the mapping from 3D reference coordinates to 2D panoramic image. In this paper, we present an innovative vision system which builds by a special combined fish-eye lenses module, and is capable of producing 3D coordinate information from the whole global observation space and acquiring no blind area 360°×360° panoramic image simultaneously just using single vision equipment with one time static shooting. It is called Panoramic Stereo Sphere Vision (PSSV). We proposed the geometric model, mathematic model and parameters calibration method in this paper. Specifically, video surveillance, robotic autonomous navigation, virtual reality, driving assistance, multiple maneuvering target tracking, automatic mapping of environments and attitude estimation are some of the applications which will benefit from PSSV.

  9. FPGA Vision Data Architecture

    Science.gov (United States)

    Morfopoulos, Arin C.; Pham, Thang D.

    2013-01-01

    JPL has produced a series of FPGA (field programmable gate array) vision algorithms that were written with custom interfaces to get data in and out of each vision module. Each module has unique requirements on the data interface, and further vision modules are continually being developed, each with their own custom interfaces. Each memory module had also been designed for direct access to memory or to another memory module.

  10. Syndrome de loge aiguë secondaire à une injection intraveineuse d ...

    African Journals Online (AJOL)

    Il s'agit d'un patient âgé de 27 ans, connu toxicomane depuis 2008 qui a présenté un syndrome de loge aigu suite à une injection d'héroïne en intraveineuse au niveau du pli du coude du membre supérieur droit. Le patient a consulté aux urgences 6 heures après l'injection d'héroïne, l'examen clinique initial a trouvé une ...

  11. Villes indiennes sous tutelle ? Une réflexion sur les échelles de gouvernance à partir des cas de Mumbai et Hyderabad

    Directory of Open Access Journals (Sweden)

    Loraine Kennedy

    2011-11-01

    contradictions, offrant un contraste saisissant avec l’image que projettent ces « visions » lisses d’une quête de développement comme un processus consensuel.There is growing recognition on the part of Indian policymakers that cities play a crucial role in the national economy, and current State (provincial policies reflect this shift. Based on two compelling, though not fully comparable, case studies of Hyderabad and Mumbai, this article argues that State governments are adopting city-centric growth strategies, following international trends. This shift raises the question of the rescaling of decision making processes as well as the emergence of metropolitan governance. Following a detailed examination of the economic and urban development strategies adopted in Mumbai and Hyderabad, the paper argues that large Indian cities are not in a sufficiently solid position to assert their political weight vis-à-vis regional government nor to seriously engage in a process of collective action at the metropolitan scale. This increasing disjunction between political and economic functions should be emphasized in the Indian context, since it marks a difference with recent European experience, at least a difference of degree if not substance. The political subordination of urban local bodies in India is exacerbated by the traditionally centralized nature of political institutions, the relative weakness of local institutions of governance (in terms of mandate and fiscal revenue, the absence of powerful mayors and the virtual nonexistence of a political entity at the metropolitan level. Furthermore, taking into account economic growth, social justice and the environment is a Herculean task, especially in a plural society. Hence, in both cities ongoing processes are contentious and contradictory, providing a stark contrast to the smooth vision statements that convey an image of the quest for “development” as a consensual process.

  12. Modeling foveal vision

    NARCIS (Netherlands)

    Florack, L.M.J.; Sgallari, F.; Murli, A.; Paragios, N.

    2007-01-01

    geometric model is proposed for an artificial foveal vision system, and its plausibility in the context of biological vision is explored. The model is based on an isotropic, scale invariant two-form that describes the spatial layout of receptive fields in the the visual sensorium (in the biological

  13. Une Nouvelle Forme d’Autobiographie dans Les Années d’Annie Ernaux: Autobiographie Impersonnelle

    Directory of Open Access Journals (Sweden)

    Seçil Yücedağ

    2017-12-01

    Full Text Available Annie Ernaux, considérée comme l’une des femmes écrivaines les plus célèbres du XXIe siècle, a exprimé l’angoisse commune de son âge et de son passé en rédigeant Les Années. Elle n’avait pas non seulement le but de décrire sa vie, mais aussi d’esquisser l’histoire de la société française à laquelle elle appartient. Lorsqu’elle est venue au monde en 1940, le monde était au seuil de la Seconde Guerre mondiale. Etant élevée dans cette atmosphère chaotique, elle a appris beaucoup de choses de sa société, de sa famille et de son environnement. Annie Ernaux a découvert le monde comme une jeune fille, une mère, une épouse et une grand-mère. Ses expériences sociales et familiales l’ont beaucoup mûrie et elle a commencé à rédiger ses pensées. Ses souvenirs ont fait partie de ses écritures autobiographiques. Dans Les Années, Annie Ernaux a profité de toutes ses expériences personnelles et sociales avec de différents moyens. Elle a essayé d’établir des liens entre l’histoire de sa vie et celle de la société. Elle a accordé une importance à la vie sociale plutôt que sa propre vie dans Les Années. Elle y a développé des propres techniques d’écriture en se servant des photos familiales et personnelles, d’un film, d’une vidéo, des marques de publicité, des chansons, d’un tableau, des notes de journal ainsi que des événements sociologiques et historiques. Elle a ainsi créé une nouvelle forme d’autobiographie : autobiographie impersonnelle.

  14. A computer vision system for rapid search inspired by surface-based attention mechanisms from human perception.

    Science.gov (United States)

    Mohr, Johannes; Park, Jong-Han; Obermayer, Klaus

    2014-12-01

    Humans are highly efficient at visual search tasks by focusing selective attention on a small but relevant region of a visual scene. Recent results from biological vision suggest that surfaces of distinct physical objects form the basic units of this attentional process. The aim of this paper is to demonstrate how such surface-based attention mechanisms can speed up a computer vision system for visual search. The system uses fast perceptual grouping of depth cues to represent the visual world at the level of surfaces. This representation is stored in short-term memory and updated over time. A top-down guided attention mechanism sequentially selects one of the surfaces for detailed inspection by a recognition module. We show that the proposed attention framework requires little computational overhead (about 11 ms), but enables the system to operate in real-time and leads to a substantial increase in search efficiency. Copyright © 2014 Elsevier Ltd. All rights reserved.

  15. The sign of Kanaimà, the space of Guayana and the demonology of development

    OpenAIRE

    Whitehead, Neil L.

    2017-01-01

    Cet essai explore la façon dont le complexe shamanique du Kanaimá devient une représentation centrale du sauvage tant dans les sociétés nationales que coloniales du nord-est de l’Amérique du Sud. En association avec le signe cannibale, Kanaimá est utilisé pour bâtir une vision de Majesté Satanique en Amazonie. Cette vision de Majesté Satanique tenant sous son pouvoir les cultures indigènes est à son tour utilisée pour produire une démonologie du développement. Cette démonologie présente la tr...

  16. Les gitans, la prison et le quartier : une relation spécifique devenue le modèle ordinaire

    OpenAIRE

    Cunha, Manuela Ivone P. da

    2005-01-01

    La portion gitane de l'univers détenu dans une prison portugaise représentait dans les anées 80 une modalité de vie carcérale qui échappait aux définitions des «institutions totales». Ce qui n'était alors qu'atypique -- et pouvant par lá même inviter à ramener cette exception à une spécificité «ethnique» -- annonçait pourtant le début d'une tendance plus vaste. Une décénnie plus tard, elle caractériserait l'ensemble de la population incarcérée. C'est cette tendance intégrant gitans et non-git...

  17. Une stratégie de développement fondée sur l’innovation

    OpenAIRE

    Schut, Pierre-Olaf

    2013-01-01

    Petzl est une entreprise du bassin Grenoblois dont l’activité est centrée sur la production de matériel de montagne. Aujourd’hui, l’entreprise est une importante PMI internationale de l’industrie des articles de sport, portée par des produits tels que les lampes frontales, les harnais d’escalade et les engins mécaniques assurant la progression sur corde. Hier, elle était une simple entreprise artisanale familiale, proposant du matériel de spéléologie. La présente monographie révèle l’évolutio...

  18. L'évaluation du fait technique : Une métaphysique pour l'hypersauvage contemporain

    OpenAIRE

    Gras , Alain

    2010-01-01

    International audience; LLe terme " évaluation " est porteur d'une ambiguïté dès l'origine car son contenu sémantique est double : donner un prix, ou une mesure, mais aussi " donner une valeur " entendu d'un point de vue éthique, la valeur dont parle Weber. Or la fascination pour la mesure occulte le fait que le choix des éléments à mesurer est subjectif et qu'en aucun cas la scientificité ne vient directement de l'observation de l'objet. Cette caractéristique subjective est tout simplement i...

  19. Impact of low vision services on the quality of life of low vision patients in Ghana

    Directory of Open Access Journals (Sweden)

    Godwin O. Ovenseri-Ogbomo

    2016-03-01

    Full Text Available Patients’ perspectives on the impact of clinical interventions have been recognised as critical elements in patient care. Quality-of-life instruments are designed to measure these perspectives. We used the National Eye Institute’s 25-item Visual Function Questionnaire (NEI VFQ to measure the impact of optical low vision devices on the quality of life of 22 low vision patients who obtained and were using low vision devices from a secondary low vision clinic in the Eastern Region, Ghana. The study employed a pre- and post-intervention technique. We found statistically significant improvements in measured visual acuity and NEI VFQ scores in 8 of the 10 domains evaluated. We conclude that optical low vision devices have a positive impact on the quality of life of low vision patients in Ghana. Keywords: low vision; quality of life; visual acuity; visual impairment; Ghana

  20. La classe dans son gymnase: une métaphore géographique

    Directory of Open Access Journals (Sweden)

    Yves POINSOT

    1996-06-01

    Full Text Available Retouchant une métaphore de J.D. Nystuen, on cherche ici, par la description imaginaire du comportement d'un groupe d'élèves placé dans un gymnase, à mettre en évidence certaines règles essentielles de la composition spatiale. Des propositions destinées à favoriser l'insertion de cet outil dans une pédagogie interdisciplinaire prolongent cette présentation.

  1. L'objectivation et la perfection des femmes dans la publicité. La perception des consommateurs vis-à-vis des femmes représentées dans des campagnes publicitaires et ses effets sur la marque et sur eux-mêmes.

    OpenAIRE

    Van Dessel, Sophie; Loir, Estelle

    2017-01-01

    Depuis son apparition, la publicité contribue consciemment ou inconsciemment au changement de perception du corps de la femme. Dans la société occidentale, utiliser le corps de la femme pour inciter à l’achat d’un produit est une pratique commune dans le marketing. Un ensemble d’effets en tous genres sont à observer sur la perception des consommateurs à propos du produit et sur la marque, sur leur perception vis-à-vis des mannequins et des femmes en général et finalement sur la perception qu’...

  2. Industrial vision

    DEFF Research Database (Denmark)

    Knudsen, Ole

    1998-01-01

    This dissertation is concerned with the introduction of vision-based application s in the ship building industry. The industrial research project is divided into a natural seq uence of developments, from basic theoretical projective image generation via CAD and subpixel analysis to a description...... is present ed, and the variability of the parameters is examined and described. The concept of using CAD together with vision information is based on the fact that all items processed at OSS have an associated complete 3D CAD model that is accessible at all production states. This concept gives numerous...... possibilities for using vision in applications which otherwise would be very difficult to automate. The requirement for low tolerances in production is, despite the huge dimensions of the items involved, extreme. This fact makes great demands on the ability to do robust sub pixel estimation. A new method based...

  3. Comment évaluer la valeur sociale d'un bien? D'une définition substantive à la construction sociale d'une procédure de qualification

    OpenAIRE

    CARATY , Mélodie; Chanteau , Jean-Pierre

    2016-01-01

    International audience; Les stratégies de responsabilité sociale des entreprises (RSE) conduisent certaines d'entre elles, comme ArcelorMittal, à se demander quelle est la ‘valeur sociale' de ses produits. Pour définir ce qu'est la valeur sociale, nous nous appuyons sur la littérature scientifique en économie dans laquelle le concept de ‘valeur' est une question canonique. Une définition objective de la valeur sociale ne peut être fournie puisqu'elle résulte d'un jugement collectif issu d'int...

  4. [Colors and their meaning in culture and psychology--a historical outline and contemporary status of color vision theories].

    Science.gov (United States)

    Grzybowski, Andrzej; Lewicka, Romana; Torlińska, Teresa; Stelcer, Bogusław

    2008-01-01

    The mechanism of color perception has intrigued scholars from antiquity. However, the understanding of this phenomena only came with the recognition of the nature of light and visual perception. Ancient concepts, present in science until the Renaissance, were based more on philosophical considerations and theoretical speculations than on anatomical studies and a matter-of-fact assessment of physiological functions of the visual system. From antiquity to 17th century scientific approach to the concept of vision was dominated by two theories: intromission and extramission (emanation). Intromission theory, propagated by Alhazen (lbn al.-Haythama), Vitello, John Peckham, Roger Bacon and Leonardo da Vinci, assumed that the light was transmitted from the observed object perpendicularly to the transparent eye structures. Johannes Kepler was the first scholar to propose that the retina was the receptive part of the eye. In the first half of the 17th century, Kepler's groundbreaking optical achievements and anatomical discoveries of many other scientists cast new light on the understanding of the role of different eye structures, finally wiping out the intromission theory. A further major achievement contributing to the recognition of the true nature of colors was a theory presented by Newton in 1688. He argued that they were colored rays, and not white light, that were composed of homogenous and pure light. It was, however, not until the 19th century when two modern theories of color appeared, i.e. a trichromatic theory mostly associated with the names of Young and Hemlholtz, and an opponent colors theory of Hering. In the 20th century, the two theories--previously assumed as contradictory--were joined into the zone theories of color vision. Colors have their cultural and social meanings, as far as a very individual and personal interpretation. In the former function they are used to illustrate some cultural and sociological phenomena; in the latter, they are helpful in

  5. Company Vision and Organizational Learning

    Directory of Open Access Journals (Sweden)

    Vojko Toman

    2015-11-01

    Full Text Available The effectiveness of a company is largely dependent on the company itself; it depends above all on its corporate governance, management, and implementation, as well as on decision-making processes and coordination. Many authors believe that organizational learning and knowledge are the most relevant aspects of company effectiveness. If a company wants to be effective it needs to create and realize its vision; to do this, it needs creativity, imagination, and knowledge, which can be obtained or enhanced through learning. This paper defines vision, learning, creativity and management and, above all, their relationships. The author argues that company vision influences the learning and knowledge of employees in the company through the vision’s content, through the vision-creating process, and through the vision enforcement process. Conversely, the influence of learning on company vision is explained. The paper is aimed at the use in the practice of companies and helps them to increase their effectiveness.

  6. Le désir au féminin : d’une « Lucrèce » à une autre

    Directory of Open Access Journals (Sweden)

    Jacqueline Fabre-Serris

    2010-11-01

    Full Text Available Cet article propose deux hypothèses. La première est celle d’une réception élégiaque du célèbre portrait livien de Lucrèce dans l’élégie 1, 3 de Tibulle. La fin de l’élégie 1, 3 constitue une variation sur un motif des Amores (la séparation des amants due à l’absence de l’homme, retenu au loin que Virgile avait évoqué dans la Bucolique 10. Dans ce passage Tibulle apporte à la question « comment se comporte alors la puella ? » une réponse inspirée par l’image que Tite-Live venait de donner, avec sa Lucrèce, de la vertu des femmes, réponse qui infléchit la scène livienne dans le sens de la passion. La seconde hypothèse est que le texte de Tibulle a été la matrice de plusieurs autres textes centrés sur la séparation, la fidélité et le désir féminin : les poèmes 3, 9 ; 3, 14 et 15 de Sulpicia ; les élégies 1, 3 ; 2, 29 et 4, 3 de Properce et le passage des Fastes consacré à Lucrèce.

  7. Understanding and preventing computer vision syndrome.

    Science.gov (United States)

    Loh, Ky; Redd, Sc

    2008-01-01

    The invention of computer and advancement in information technology has revolutionized and benefited the society but at the same time has caused symptoms related to its usage such as ocular sprain, irritation, redness, dryness, blurred vision and double vision. This cluster of symptoms is known as computer vision syndrome which is characterized by the visual symptoms which result from interaction with computer display or its environment. Three major mechanisms that lead to computer vision syndrome are extraocular mechanism, accommodative mechanism and ocular surface mechanism. The visual effects of the computer such as brightness, resolution, glare and quality all are known factors that contribute to computer vision syndrome. Prevention is the most important strategy in managing computer vision syndrome. Modification in the ergonomics of the working environment, patient education and proper eye care are crucial in managing computer vision syndrome.

  8. UNDERSTANDING AND PREVENTING COMPUTER VISION SYNDROME

    Directory of Open Access Journals (Sweden)

    REDDY SC

    2008-01-01

    Full Text Available The invention of computer and advancement in information technology has revolutionized and benefited the society but at the same time has caused symptoms related to its usage such as ocular sprain, irritation, redness, dryness, blurred vision and double vision. This cluster of symptoms is known as computer vision syndrome which is characterized by the visual symptoms which result from interaction with computer display or its environment. Three major mechanisms that lead to computer vision syndrome are extraocular mechanism, accommodative mechanism and ocular surface mechanism. The visual effects of the computer such as brightness, resolution, glare and quality all are known factors that contribute to computer vision syndrome. Prevention is the most important strategy in managing computer vision syndrome. Modification in the ergonomics of the working environment, patient education and proper eye care are crucial in managing computer vision syndrome.

  9. [Quality system Vision 2000].

    Science.gov (United States)

    Pasini, Evasio; Pitocchi, Oreste; de Luca, Italo; Ferrari, Roberto

    2002-12-01

    A recent document of the Italian Ministry of Health points out that all structures which provide services to the National Health System should implement a Quality System according to the ISO 9000 standards. Vision 2000 is the new version of the ISO standard. Vision 2000 is less bureaucratic than the old version. The specific requests of the Vision 2000 are: a) to identify, to monitor and to analyze the processes of the structure, b) to measure the results of the processes so as to ensure that they are effective, d) to implement actions necessary to achieve the planned results and the continual improvement of these processes, e) to identify customer requests and to measure customer satisfaction. Specific attention should be also dedicated to the competence and training of the personnel involved in the processes. The principles of the Vision 2000 agree with the principles of total quality management. The present article illustrates the Vision 2000 standard and provides practical examples of the implementation of this standard in cardiological departments.

  10. O papel da une no movimento estudantil na segunda metade do séc. XX

    Directory of Open Access Journals (Sweden)

    Lúcia Rangel Azevedo

    2010-07-01

    Full Text Available This article tries to introduce the student movements inside the politician scenario of Brazil from 1950 to 1985. We started this presentation focusing the political facts between 1954 and 1964 trying to build a framework about the situation of the country by this time. The performance of UNE involves not only the educational question but also the social, political and economic Brazilian reality. UNE gets to a very important position in the country because of its participation in the discussion of the Brazilian problems. By 1964, a ‘coup d’etat’ throws the country into a military dictatorship, which lasts for 21 years. This modifies all the educational structure of the country and challenges UNE in many ways. The students use UNE to try to get the university reform and also to find a solution for the problem of the students who get approved in the tests to get into the universities but can’t do it because there’s no space for all the students. Finally, we’ve discussed the performance of UNE till 1985, calling attention of our readers to the small interest of our students to the problems of our country.

  11. Réjouissons-nous d'une initiative visant à introduire un système ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    4 déc. 2017 ... Heartfile a assumé le coût d'une intervention chirurgicale pour une malformation cardiaque, et il peut de nouveau pratiquer son sport préféré, le cricket. Photo: CRDI / Tom Pilston. Onze hôpitaux sont inscrits au programme de Heartfile dans trois des quatre provinces pakistanaises, et les opérations ...

  12. La cohésion sociale : une solution ou un moteur de violence urbaine ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    La cohésion sociale : une solution ou un moteur de violence urbaine ? 28 septembre 2016. Image. un policer qui gère une foule. Shaun Swingler. COLLECTION: HISTOIRE À SUCCÈS | VILLES SÛRES ET INCLUSIVES. La cohésion sociale peut jouer un rôle important dans l'établissement et le maintien de l'ordre dans les ...

  13. Baudolino, les rois mages et le mentir vrai.Pour une lecture du signe

    Directory of Open Access Journals (Sweden)

    Arnaud de Vallouit

    2003-09-01

    Full Text Available Quels sont les rapports entre la parole et la réalité dans le quatrième roman d’Umberto Eco, Baudolino ? L’écrivain brouille ostensiblement les pistes dans un ouvrage expérimental, qui est une méditation sur la création littéraire, mais reste prisonnier d’une forme finalement assez conventionnelle.

  14. [Comparison of the Pressure on the Larynx and Tongue Using McGRATH® MAC Video Laryngoscope--Direct Vision versus Indirect Vision].

    Science.gov (United States)

    Tanaka, Yasutomo; Miyazaki, Yukiko; Kitakata, Hidenori; Shibuya, Hiromi; Okada, Toshiki

    2015-12-01

    Studies show that McGRATH® MAC (McG) is useful during direct laryngoscopy. However, no study has examined whether McG re- duces pressure on the upper airway tract We compared direct vision with indirect vision concerning pressure on the larynx and tongue. Twenty two anesthesiologists and 16 junior residents attempted direct laryngoscopy of airway management simulator using McG with direct vision and indirect vision. Pressure was measured using pressure measurement film. In anesthesiologists group, pressure on larynx was 14.8 ± 2.7 kgf · cm(-2) with direct vision and 12.7 ± 2.7 kgf · cm(-2) with indirect vision (P vision and 7.6 ± 2.8 kgf · cm(-2) with indirect vision (P = 0.18). In junior residents group, pressure on larynx was 19.0 ± 1.3 kgf · cm(-2) with direct vision and 14.1 ± 3.1 kgf · cm(-2) with indirect vision (P vision and 11.2 ± 4.7 kgf · cm(-2) with indirect vision (P vision can reduce pressure on the upper airway tract.

  15. Le Cosmos d'Alexandre von Humboldt et La Tentation de saint Antoine de Gustave Flaubert : deux œuvres de toute une vie

    Directory of Open Access Journals (Sweden)

    Mary Orr

    2010-12-01

    Full Text Available Dans le septième et dernier tableau de La Tentation de saint Antoine de 1874, la fin célèbre est mise en contexte par une description longue et détaillée qui n’a jamais attiré l’attention critique qu’elle mérite. Cet article analyse l’importance de ce panorama du monde naturel sous la forme d’une exploration intertextuelle des passages du Cosmos d’Alexandre de Humboldt. Que Flaubert signale ses lectures de l’œuvre de Humboldt dans sa Correspondance de 1860 suggère des liens très riches entre Le Cosmos – que Humboldt désigne comme « l’œuvre de ma vie » – et la Tentation de saint Antoine définitive que Flaubert retravaillait au même moment. Cette relecture de La Tentation à travers la perspective de Humboldt souligne la place importante du Cosmos parmi les découvertes et les textes scientifiques contemporains de Flaubert, et la manière dont ceux-ci informent la vision de la vie scientifique et religieuse de son protagoniste, Antoine.In the seventh and final tableau of the Tentation de Saint Antoine of 1874, the famous finale is set in the context of a long, detailed description which has not attracted the critical attention it deserves. This article focuses on the importance of this panorama of the natural world as an intertextual exploration of passages from Kosmos by Alexander von Humboldt. The fact that Flaubert’s Correspondance of 1860 mentions his reading of Humboldt’s works suggests rich lines of investigation between Kosmos – which Humboldt calls the « work of all of life » and the final Tentation de Saint Antoine,which Flaubert was reworking at the same moment. This re-reading of the Tentation through the optic of Humboldt underscores the pivotal position of Kosmos amid the scientific discoveries and texts contemporary to Flaubert, and how these inform the vision of life of his protagonist, Antoine, as scientific and religious.

  16. Ecritures hétérogènes et vision une dans l’œuvre poétique de William Blake

    Directory of Open Access Journals (Sweden)

    Patrick Menneteau

    1999-01-01

    Full Text Available L’écriture poétique de William Blake est d’abord hétérogène au sens de multiple et de variée : pastorale, argumentaire démonstratif, poèmes pour enfants, discours didactiques, épopées lyriques, exhortations sont autant de modes qui se déclinent de façon apparemment désordonnée dans son œuvre. Les parodies bibliques ou swedenborgiennes, les imitations de genres littéraires bien établis et le recours au procédé de la parabole ne doivent cependant pas masquer le fait que derrière cette diversité, se trouvent une thématique et un objectif qui confèrent à l’ensemble poétique son unité. C’est en effet dans une fonction transformatrice, qui passe en particulier par la lutte contre les habitudes de pensée (et d’écriture, que se situe l’enjeu central des poèmes. Est alors hétérogène l’écriture qui, conditionnée par une lecture menée en fonction d’états spirituels identifiés par le poète, engendre l’autre (le « soi » face au « je », puis l’Autre Lui-même. Devant cet objet qui lui échappe, c’est enfin l’écriture de la critique qui devient nécessairement hétérogène.William Blake’s poetical writing is heterogeneous firstly in the sense of varied and multiple: pastorals, demonstrative arguments, children’s poems, didactic pieces, lyrical epics, exhortations are as many different modes of writing which the poet uses in an apparently disorderly fashion. Nevertheless, the biblical and Swedenborgian parodies, the imitations of well-established genres and the use of the parable should not conceal the fact that under the diversity lie a number of set themes and an objective which ensure the unit y of the works. Indeed, the central stake of these poems is to be found in a transformative function, which implies the denial of our habits of thinking and writing. Heterogeneous is then the mode of writing which, being determined by a practice of reading related to the spiritual states

  17. Stereo Vision Inside Tire

    Science.gov (United States)

    2015-08-21

    1 Stereo Vision Inside Tire P.S. Els C.M. Becker University of Pretoria W911NF-14-1-0590 Final...Stereo Vision Inside Tire 5a. CONTRACT NUMBER W911NF-14-1-0590 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER 6. AUTHOR(S) Prof PS Els CM...on the development of a stereo vision system that can be mounted inside a rolling tire , known as T2-CAM for Tire -Terrain CAMera. The T2-CAM system

  18. Copenhagen Energy Vision

    DEFF Research Database (Denmark)

    Mathiesen, Brian Vad; Lund, Rasmus Søgaard; Connolly, David

    The short-term goal for The City of Copenhagen is a CO2 neutral energy supply by the year 2025, and the long-term vision for Denmark is a 100% renewable energy (RE) supply by the year 2050. In this project, it is concluded that Copenhagen plays a key role in this transition. The long-term vision...

  19. Développer et personnaliser les compétences info-communicationnelles des enseignants de français langue étrangère – un impératif face à une mutation des publics apprenant au Centre du Vietnam

    Directory of Open Access Journals (Sweden)

    HOANG Thi Thu Hanh

    2016-12-01

    Full Text Available Selon notre témoignage, le nombre d’apprenants de FLE au centre du Vietnam ne baisse pas mais les objectifs et les motivations ont changé et bien varié. Vu les débouchés francophones, il y a moins d’étudiants qui choisissent comme leur première option d’études universitaires les sciences du langage français et la didactique du FLE, mais de plus en plus nombreux sont ceux qui étudient le français comme un moyen de se professionnaliser et ou pour un objectif personnel (étudier ou faire un stage dans un pays francophone, consulter les documents en français, communiquer avec la clientèle francophone, participer à des réseaux sociaux, etc.. Cette situation témoigne d’une évolution des attentes où s’expriment un pouvoir d’action élargie et l’intégration dans un monde global largement numérisé. Se dessine ainsi progressivement une nouvelle voie pour l’apprentissage du FLE,résultat d’une convergence entre notre héritage culturel complexe et un milieu technique devenu un lieu de sociabilité sans précédent. Ces dernières années, plusieurs courants de pensée se sont intéressés à l’essor des TICE et à l’explosion des pratiques info-communicationnelles. Deux concepts dominent : l’information litéracy anglo-saxonne et nord-américaine et la culture de l’information francophone et européenne. La première, plus utilitariste, est centrée sur l’opérationnel dans une société de la connaissance ; la seconde propose de sortir d’une vision techniciste de la communication et vise le développement non seulement de compétences mais aussi de connaissances pour un monde ouvert. Compétences et connaissances que les enseignants doivent dorénavant maitriser avant de les transmettre.

  20. Vision/INS Integrated Navigation System for Poor Vision Navigation Environments

    Directory of Open Access Journals (Sweden)

    Youngsun Kim

    2016-10-01

    Full Text Available In order to improve the performance of an inertial navigation system, many aiding sensors can be used. Among these aiding sensors, a vision sensor is of particular note due to its benefits in terms of weight, cost, and power consumption. This paper proposes an inertial and vision integrated navigation method for poor vision navigation environments. The proposed method uses focal plane measurements of landmarks in order to provide position, velocity and attitude outputs even when the number of landmarks on the focal plane is not enough for navigation. In order to verify the proposed method, computer simulations and van tests are carried out. The results show that the proposed method gives accurate and reliable position, velocity and attitude outputs when the number of landmarks is insufficient.